Extended Queueing of Handover (EQH) Scheme
In a handover process, a UT with unfulfilled handover request will have its call terminated once it leaves the present cell i.e. when the signal strength of the present beam drops below an acceptable level. Under the proposed Extended Queueing of Handover (EQH) scheme [5], the policies of queueing and early channel reservation also apply to handover calls. In addition to them, the queueing process of an initially unfulfilled handover is allowed to be continued in the destination cell and thus lasts longer, promising a higher chance of obtaining a free communication channel. In this case, since the UT has left the present cell and has not reserved a channel from the destination cell,
its call has to be discontinued until either a free channel is available on which the call can be resumed on,or until the tolerable suspension period is over which the call has to be permanently terminated,whichever comes first. Although this suspended call is prioritised over new call in getting a channel, it does not significantly affect the blocking rate of new call because the probability that a call get suspended is very small. From the viewpoints of the two involved communicating parties in an initially unsuccessful handover call,
the discontinuity can be notified through a special tone / message. In terms of quality of service (QoS), a suspended call that eventually gets terminated is better than a disruptive and uninformed drop call. On the other hand, if the call is able to be resumed upon the availability of an idle channel, the short term discontinuity makes it worth than having the call terminated and followed by setting up a new call again, which is harder because new call is less privileged. Hence regardless of the outcome EQH scheme promises a higher QoS.
Friday, August 27, 2010
General aspects of mobile satellite systems
General aspects of mobile satellite systems
Differences between satellite and terrestrial systems exist in spite of common objectives for high quality services and excellent spectrum efficiency. Some differences arise because:- user costs are closely related to satellite transmit power the satellite propagation channel is highly predictable satellite paths introduce significant propagation delays and Doppler shifts frequency co-ordination has to be on a global basis frequency re-use options are more limited, hence bandwidth is a tight constraint satellite beam shaping and sizing opportunities are limited.The first two points lead naturally to the emphasis placed on the line-of-sight satellite link budget when establishing the system design. The base link budget is derived from theoretical path losses to which link margins are added to
compensate for inevitable impairments in equipment and propagation characteristics. All impairments, even if not directly calculable in terms of signal loss (e.g. group delay and rate of change of Doppler shift), are converted accurately to dB so that the compensating increase in transmit power can be established. The total margin over the theoretical ideal
path is only a few dB and precision in calculating the contributory impairments is essential. The resulting link budget then allows the availability and quality of service to be estimated over the coverage area.Large link margins have a major impact on system build cost and operating tariffs simply because of the impact of additional power requirements on spacecraft size — a 3dB excess margin would almost double user charges. For this reason, mobile satellite communication systems have lead the way in very power-efficient modulation formats and low bit rate voice codecs (2,4 kbit/s and 4,8 kbit/s) as well as adaptive power control. The drive for efficient use of satellite power is noticeably reflected in terminal equipment design with:
- very low loss antennas coupled with very low loss receive filters;
- very tight transmit/receive filter specifications;
- very low noise amplifiers;
- excellent carrier/signal acquisition in presence of Doppler, noise and interference;
- power-saving and spectrum-efficient forward error correction;
- multi-path discrimination techniques might facilitate low signal-to-noise demodulator operation
The satellite-mobile uplink and downlink are inevitably more fragile than the corresponding feeder links (land earth station-satellite). However the feeder link itself needs a very substantial link margin in order that the aggregate up/down performance may be largely determined by the mobile link. These feeder links operate in higher frequency bands where Doppler and atmospheric/meteorological disturbances can become even more significant. The following clauses of this TR focus on particular characteristics, capabilities and limitations of mobile satellite systems together with typical values for key parameters where possible. However it must be recognised that most parameters are inter-dependent and will also vary with architecture of the ground infrastructure, the satellite orbital arrangement, and the user terminal configuration.
Differences between satellite and terrestrial systems exist in spite of common objectives for high quality services and excellent spectrum efficiency. Some differences arise because:- user costs are closely related to satellite transmit power the satellite propagation channel is highly predictable satellite paths introduce significant propagation delays and Doppler shifts frequency co-ordination has to be on a global basis frequency re-use options are more limited, hence bandwidth is a tight constraint satellite beam shaping and sizing opportunities are limited.The first two points lead naturally to the emphasis placed on the line-of-sight satellite link budget when establishing the system design. The base link budget is derived from theoretical path losses to which link margins are added to
compensate for inevitable impairments in equipment and propagation characteristics. All impairments, even if not directly calculable in terms of signal loss (e.g. group delay and rate of change of Doppler shift), are converted accurately to dB so that the compensating increase in transmit power can be established. The total margin over the theoretical ideal
path is only a few dB and precision in calculating the contributory impairments is essential. The resulting link budget then allows the availability and quality of service to be estimated over the coverage area.Large link margins have a major impact on system build cost and operating tariffs simply because of the impact of additional power requirements on spacecraft size — a 3dB excess margin would almost double user charges. For this reason, mobile satellite communication systems have lead the way in very power-efficient modulation formats and low bit rate voice codecs (2,4 kbit/s and 4,8 kbit/s) as well as adaptive power control. The drive for efficient use of satellite power is noticeably reflected in terminal equipment design with:
- very low loss antennas coupled with very low loss receive filters;
- very tight transmit/receive filter specifications;
- very low noise amplifiers;
- excellent carrier/signal acquisition in presence of Doppler, noise and interference;
- power-saving and spectrum-efficient forward error correction;
- multi-path discrimination techniques might facilitate low signal-to-noise demodulator operation
The satellite-mobile uplink and downlink are inevitably more fragile than the corresponding feeder links (land earth station-satellite). However the feeder link itself needs a very substantial link margin in order that the aggregate up/down performance may be largely determined by the mobile link. These feeder links operate in higher frequency bands where Doppler and atmospheric/meteorological disturbances can become even more significant. The following clauses of this TR focus on particular characteristics, capabilities and limitations of mobile satellite systems together with typical values for key parameters where possible. However it must be recognised that most parameters are inter-dependent and will also vary with architecture of the ground infrastructure, the satellite orbital arrangement, and the user terminal configuration.
Who will use satellite communications systems?
Who will use satellite communications systems?
Global roamer
The first type of satellite user will be the global roamer. The global roamer consists mainly of business travelers who want to have the ability to make and receive calls anywhere in the world. Iridium has conducted extensive analysis of this market and concluded that this market will consist of 42 million people by the year 2002.
Cellular extension
The second type of user will be individuals who wish to extend their cellular coverage to areas where no service currently exists. Both Globalstar and Iridium plan to offer dual mode phones which will work with GSM/TDMA/CDMA cellular systems and satellite communications systems. An example of a dual mode user would be would be an individual who lives in Chicago and travels to upstate Montana for a hunting trip. The
person would normally have cellular service from Ameritech but that coverage does not include upstate Montana where no cellular coverage exists. To be able to receive service on their Ameritech system (same phone number) in Montana, the individual would sign up with Iridium for dual mode service. Signing up would mean that once the
individual got out of the range of their Ameritech systems, they could hit a switch on their Iridium phone and make or receive calls outside of their Ameritech coverage zone routed through the Iridium satellite system. This would allow for ubiquitous service for cellular users even when they are out of range of their current cellular system.
Landline extension
The third type of satellite user will an individual who wants landline extension. In this instance a satellite company would install a fixed telephone booth in a rural area (e.g. in the outskirts of India). This would enable a rural town, which currently has no means of voice communications, to communicate with an urban area where medical, police or other services exist. The rural town could also use the phone to call suppliers of staple products. Fixed satellite service would mostly be used when a landline system is uneconomical or technologically incapableor serving a particular location. Vodaphone has been using fixed wireless phone booths in South Africa and has averaged 800 minutes of use per booth.
Global roamer
The first type of satellite user will be the global roamer. The global roamer consists mainly of business travelers who want to have the ability to make and receive calls anywhere in the world. Iridium has conducted extensive analysis of this market and concluded that this market will consist of 42 million people by the year 2002.
Cellular extension
The second type of user will be individuals who wish to extend their cellular coverage to areas where no service currently exists. Both Globalstar and Iridium plan to offer dual mode phones which will work with GSM/TDMA/CDMA cellular systems and satellite communications systems. An example of a dual mode user would be would be an individual who lives in Chicago and travels to upstate Montana for a hunting trip. The
person would normally have cellular service from Ameritech but that coverage does not include upstate Montana where no cellular coverage exists. To be able to receive service on their Ameritech system (same phone number) in Montana, the individual would sign up with Iridium for dual mode service. Signing up would mean that once the
individual got out of the range of their Ameritech systems, they could hit a switch on their Iridium phone and make or receive calls outside of their Ameritech coverage zone routed through the Iridium satellite system. This would allow for ubiquitous service for cellular users even when they are out of range of their current cellular system.
Landline extension
The third type of satellite user will an individual who wants landline extension. In this instance a satellite company would install a fixed telephone booth in a rural area (e.g. in the outskirts of India). This would enable a rural town, which currently has no means of voice communications, to communicate with an urban area where medical, police or other services exist. The rural town could also use the phone to call suppliers of staple products. Fixed satellite service would mostly be used when a landline system is uneconomical or technologically incapableor serving a particular location. Vodaphone has been using fixed wireless phone booths in South Africa and has averaged 800 minutes of use per booth.
Friday, August 20, 2010
1 smartcard
11. Applications on Linux
In this section there will be applications that uses smart cards for some reason on Linux environment. If you are a developer of a software and your development environment is Linux please let me know. I will add you in the list.
11.1. scas
SCAS is a simple program that checks the code inside the card with the code inside the computer. As an example of showing a way of authentication with memory cards scas is very good.
11.2. smartcard
smartcard is a general smart card utility in Linux which uses CT-API. With smartcard utility you can read/write data from/into smart cards. As long as your reader can be accessed via CT-API, smartcard can be used to control the reader. Currently smartcard could only be used with memory cards using I2C or 3W protocols. There is also a GTK+/Gnome graphical front end which support all functions of smartcard utility.
11.3. ssh-smart
ssh-smart is a basic proof-of-concept of ssh identity on smart card, as the author says. ssh-smart uses smartcard utility to communicate with the smart card. Basically, ssh-smart-add tool (perl script) call ssh-keygen to generate RSA public and private keys. Than puts the private key on the memory card. Later the ssh-smart-addagent tool can be used to extract the private key from the card to use with ssh-agent.
11.4. smarttools-rsa
This is another PAM Module for Unix systems but supports RSA authentication through your private key on the smart card. You must have a Schlumberger Cyberflex Access card or Schlumberger Cryptoflex for Windows Card and a working reader to use this tool.
11.5. smartsign
This utility is some-complete PKI integration with the smart cards. To use you must establish a working OpenCA and have Schlumberger's "Cyberflex Access 16K" smart cards. During the certification process of OpenCA, private key and public certificate can be stored on the smart card and private key, later, could be used with Netscape to sign outgoing mails and news. Also smartsign supports authentication of local users via a PAM Module through a public key authentication. Smartsign comes with gpkcs11, a PKCS#11 implementation, smastsh, a command line shell that allows browsing smart card contents, sign_sc/verify_sc to sign and verify any file with smart card.
11.6. CITI Projects
At CITI, Center for Information Technology Integration of Michigan University, there are some new projects. For example, Webcard is a web server running on a Schlumberger Cyberflex Access Java Card. Features a stripped TCP/IP stack that supports HTTP only. The system is designed to have a router which frames IP packets in ISO7816 and a Java Virtual Machine in the card. Detailed technical report can be found at
In this section there will be applications that uses smart cards for some reason on Linux environment. If you are a developer of a software and your development environment is Linux please let me know. I will add you in the list.
11.1. scas
SCAS is a simple program that checks the code inside the card with the code inside the computer. As an example of showing a way of authentication with memory cards scas is very good.
11.2. smartcard
smartcard is a general smart card utility in Linux which uses CT-API. With smartcard utility you can read/write data from/into smart cards. As long as your reader can be accessed via CT-API, smartcard can be used to control the reader. Currently smartcard could only be used with memory cards using I2C or 3W protocols. There is also a GTK+/Gnome graphical front end which support all functions of smartcard utility.
11.3. ssh-smart
ssh-smart is a basic proof-of-concept of ssh identity on smart card, as the author says. ssh-smart uses smartcard utility to communicate with the smart card. Basically, ssh-smart-add tool (perl script) call ssh-keygen to generate RSA public and private keys. Than puts the private key on the memory card. Later the ssh-smart-addagent tool can be used to extract the private key from the card to use with ssh-agent.
11.4. smarttools-rsa
This is another PAM Module for Unix systems but supports RSA authentication through your private key on the smart card. You must have a Schlumberger Cyberflex Access card or Schlumberger Cryptoflex for Windows Card and a working reader to use this tool.
11.5. smartsign
This utility is some-complete PKI integration with the smart cards. To use you must establish a working OpenCA and have Schlumberger's "Cyberflex Access 16K" smart cards. During the certification process of OpenCA, private key and public certificate can be stored on the smart card and private key, later, could be used with Netscape to sign outgoing mails and news. Also smartsign supports authentication of local users via a PAM Module through a public key authentication. Smartsign comes with gpkcs11, a PKCS#11 implementation, smastsh, a command line shell that allows browsing smart card contents, sign_sc/verify_sc to sign and verify any file with smart card.
11.6. CITI Projects
At CITI, Center for Information Technology Integration of Michigan University, there are some new projects. For example, Webcard is a web server running on a Schlumberger Cyberflex Access Java Card. Features a stripped TCP/IP stack that supports HTTP only. The system is designed to have a router which frames IP packets in ISO7816 and a Java Virtual Machine in the card. Detailed technical report can be found at
2 smartcard
12. Smart Card Uses
Literally, billions of smart cards are already in use. Worldwide smart card sales could reach 1.6 billion units in 1998, up 23% from 1.3 billion units in 1997. Western Europe accounts for about 70% of the current smart card uses, followed by South America and Asia with about 10% each, while North America languishes at less than 5%. However, most smart cards issued today are memory cards (see Table) with limited processing capabilities. Still, hundreds of millions of processor cards are already in use today.
Smart Cards Issued in 1996 (in million units)
____________________________________
Phone cards 605
Health cards 70
Banking 40
ID/access cards 20
Pay TV cards 20
GSM cards (mobile phone) 20
Transportation 15
Metering/vending 10
Others 10
------------------------------------
Total 810
____________________________________
Source: Smart Card Industry Association
Phone cards have become ubiquitous in Western Europe and Asia where coin-operated public phones are becoming nearly obsolete. These pre-paid cards increase payphone operator revenues, allow more sophisticated transactions via public phones, and have become advertising devices as well as collector's items. Although the popularity of phone cards contributed to a widening acceptance of smart cards by consumers, however, processor cards are projected to be the fastest growing smart card uses by the year 2000.
Literally, billions of smart cards are already in use. Worldwide smart card sales could reach 1.6 billion units in 1998, up 23% from 1.3 billion units in 1997. Western Europe accounts for about 70% of the current smart card uses, followed by South America and Asia with about 10% each, while North America languishes at less than 5%. However, most smart cards issued today are memory cards (see Table) with limited processing capabilities. Still, hundreds of millions of processor cards are already in use today.
Smart Cards Issued in 1996 (in million units)
____________________________________
Phone cards 605
Health cards 70
Banking 40
ID/access cards 20
Pay TV cards 20
GSM cards (mobile phone) 20
Transportation 15
Metering/vending 10
Others 10
------------------------------------
Total 810
____________________________________
Source: Smart Card Industry Association
Phone cards have become ubiquitous in Western Europe and Asia where coin-operated public phones are becoming nearly obsolete. These pre-paid cards increase payphone operator revenues, allow more sophisticated transactions via public phones, and have become advertising devices as well as collector's items. Although the popularity of phone cards contributed to a widening acceptance of smart cards by consumers, however, processor cards are projected to be the fastest growing smart card uses by the year 2000.
3 smartcard
13. Technology and Players
For smart cards to carry out applications, several components must come together. The technology of smart cards include four critical segments.
13.1. Card Manufacturers
A smart card begins with a micro-controller produced by semiconductor manufacturers such as Siemens, Motorola and Thomson. This integrated circuit chip is attached to an electronic module by inserting into a cavity on the module. Then, terminals between the chip and the electronic module are interconnected. Finally, the chip-embedded electronic module is glued to a plastic card. The global leader in card manufacturing is Schlumberger who sold about half of all smart cards in use in 1997. A close second is Gemplus followed by Bull and De La Rue of France.
13.2. Card Terminals and Readesr
Smart cards may be read by conventional card reader or by wireless terminals. New devices similar to a floppy disk allow smart cards to be read by PC disk drive. Suppliers of POS and ATM card readers have expanded into smart card readers for their product lines, where some worldwide consolidation is occurring. For example, a market leader Grupe Ingenico is buying another player De La Rue of France.
13.3. Interface between Card and Terminal (API)
Electronic modules embedded in smart cards have contacts by which messages are exchanged between the card's IC chip and the card reader. International standards such as ISO 7816 have specified which contact handles what type of data but applications must be programmed to manage message exchanges that can be used by networked processors. An interoperable and multi-platform application programming interface (API) is critical for smart cards to carry out diverse functions. Open standards such as Java smart card API provides one of several proposed interfaces. Java Card API in particular offers a development tool for flexible, multi-platform applications–"Write Once, Run Anywhere"–for devices ranging from Network Computers, Web TV, smart phones and other consumer appliances. The industry leader Schlumberger, for example, has introduced EasyFlex and FastOS based on Java API.
13.4. Applications
The ultimate utility of smart cards is in the functions they carry out–for example, payment process, identification, network computing, health care management, benefits distribution and so on. Application programs handle data read by smart card readers and forward them to central computers located at the other end of the smart card infrastructure such as payment servers in banks, traffic control centers or mobile phone centers, credit card companies, transit authorities, governments, Microsoft and other service providers. Market players and stake holders in this end game for smart cards include a wide variety of firms and institutions including card issuers, content providers, Visa and MasterCard, banks, government agencies, security implementers such as Lucent Technologies, electronics manufacturers such as NEC, and service providers who want to exploit advantages of smart card technologies.
For smart cards to carry out applications, several components must come together. The technology of smart cards include four critical segments.
13.1. Card Manufacturers
A smart card begins with a micro-controller produced by semiconductor manufacturers such as Siemens, Motorola and Thomson. This integrated circuit chip is attached to an electronic module by inserting into a cavity on the module. Then, terminals between the chip and the electronic module are interconnected. Finally, the chip-embedded electronic module is glued to a plastic card. The global leader in card manufacturing is Schlumberger who sold about half of all smart cards in use in 1997. A close second is Gemplus followed by Bull and De La Rue of France.
13.2. Card Terminals and Readesr
Smart cards may be read by conventional card reader or by wireless terminals. New devices similar to a floppy disk allow smart cards to be read by PC disk drive. Suppliers of POS and ATM card readers have expanded into smart card readers for their product lines, where some worldwide consolidation is occurring. For example, a market leader Grupe Ingenico is buying another player De La Rue of France.
13.3. Interface between Card and Terminal (API)
Electronic modules embedded in smart cards have contacts by which messages are exchanged between the card's IC chip and the card reader. International standards such as ISO 7816 have specified which contact handles what type of data but applications must be programmed to manage message exchanges that can be used by networked processors. An interoperable and multi-platform application programming interface (API) is critical for smart cards to carry out diverse functions. Open standards such as Java smart card API provides one of several proposed interfaces. Java Card API in particular offers a development tool for flexible, multi-platform applications–"Write Once, Run Anywhere"–for devices ranging from Network Computers, Web TV, smart phones and other consumer appliances. The industry leader Schlumberger, for example, has introduced EasyFlex and FastOS based on Java API.
13.4. Applications
The ultimate utility of smart cards is in the functions they carry out–for example, payment process, identification, network computing, health care management, benefits distribution and so on. Application programs handle data read by smart card readers and forward them to central computers located at the other end of the smart card infrastructure such as payment servers in banks, traffic control centers or mobile phone centers, credit card companies, transit authorities, governments, Microsoft and other service providers. Market players and stake holders in this end game for smart cards include a wide variety of firms and institutions including card issuers, content providers, Visa and MasterCard, banks, government agencies, security implementers such as Lucent Technologies, electronics manufacturers such as NEC, and service providers who want to exploit advantages of smart card technologies.
4 smartcard
14. Smart Card Advantages
Compared to conventional data transmission devices such as magnetic-stripe cards, smart cards offer enhanced security, convenience and economic benefits. In addition, smart card-based systems are highly configurable to suit individual needs. Finally, the multifunctionality as payment, application and networking devices renders a smart card as a perfect user interface in a mobile, networked economy.
14.1. Customer Benefits
14.1.1 Full Portability of Services
The smart card effectively breaks the link between the subscriber and the terminal, allowing the use of any properly equipped terminal and helping to realize the wireless promise of any-time, anywhere communications. In fact, subscribers need not be constrained to using voice terminals only. A variety of other mobile communications devices such as personal digital assistants (PDAs) and personal intelligent communicators (PICs) are available that may have voice communications added as an integral part of their capabilities. If these other devices are equipped for smart cards, the potential for communications is increased. Similarly, data communications applications could benefit from the security features inherent in smart cards.
14.1.2 International Roaming
Wireless customers often require the ability to place and receive calls when traveling abroad. For these customers, international roaming enabled by smart cards is quite valuable. For example, Ameritech, AT&T, and GTE have all instituted international roaming programs using GSM phones and smart cards. The program uses co-branded smart cards, which corporate customers bring with them when they travel abroad. Customers are given a telephone number from a GSM carrier, which allows them to be contacted in any of the countries that have international roaming agreements.
14.1.3 Intersystem Roaming
The incompatibility of different communications radio interfaces and authentication protocols (time division multiple access [TDMA], code division multiple access [CDMA], GSM, personal digital cellular [PDC], mobile satellite systems, etc.) requires subscribers to make choices that constrain them to use only one particular type of handset that works with only one radio interface. With a smart card, it becomes possible for subscribers to use one handset for different interfaces and protocols. This feature is already implemented among the three frequencies used by the GSM platform (900, 1800, and 1900 MHz). American National Standards Institute (ANSI) telephone industry price index (T1P1).3 has recommended standards for a user identity module, a smart card that can be used with the major radio access methods. Thus, it becomes conceivable to have current GSM smart cards modified so that they can work with a CDMA handset. For example, North American GSM operators have designed a process to which the SIM holds both the GSM and advanced mobile phone service (AMPS) authentication algorithm and data to provide authentication on both networks in interroaming situations.
14.1.4 Multiple Services on a Single Card
As mentioned earlier, maximum value is realized by the subscriber when multiple applications are stored on a single card (see Figure). A multiapplication smart card could provide access to airline reservation and ticketing systems and information networks, as well as a mobile telephone service. Considering the many cards that the average person carries these days (i.e., numerous credit cards, debit cards, employee ID cards), integrating more applications into a single card (or at least fewer cards) has obvious appeal and benefits. It is important to note that there is clear interest on the part other industries to package their services with mobile telephony. For example, research by Citibank indicates clearly that a substantial percentage of the company's customers would like to be able to conduct its banking on a variety of platforms, including wireless. Such services are already available using a standardized toolbox for smart-card application creation.
14.1.5 Separation of Business and Personal Calls
The smart card allows customers to be billed separately for personal and business calls made on a single phone. For example, Airtel, a Spanish GSM operator, uses a SIM card with two sets of subscription information—one for corporate and the other for personal use. Airtel’s dual SIM cards have been well received in the corporate market.
14.2 Enhanced Security Benefits
SIM cards have several features that enhance security for wireless communications networks. Smart-card supporters point to the potential of limiting or eliminating fraud as one of their strongest selling points.
SIM cards provide a secure authentication key transport container from the carrier’s authentication center to the end-user’s terminal. Their superior fraud protection is enabled by hosting the cryptographic authentication algorithm and data on the card’s microprocessor chip. SIM cards can be personal identification number (PIN) protected and include additional protection against logical attacks. With added PIN code security, SIM cards offer the same level of security used by banks for securing off-line payments.
Because the home network–authentication algorithm also resides in the card, SIM cards make secure roaming possible. They can also include various authentication mechanisms for internetwork roaming of different types.
Complete fraud protection (with the exclusion of subscription fraud) can only be provided in the context of a complete security framework that includes terminal authentication, an authentication center, and authentication key management. Smart cards are an essential piece of this environment, but only the complete architecture can allow fraud reduction and secure roaming.
Finally, it should be noted that biometric smart-card applications such as voice or fingerprint recognition could be added to provide maximum fraud prevention. Smart cards could then combine the three basic security blocks of possession, knowledge, and characteristics (see Figure ).
14.3 Convenience
One use of the old fashioned memory cards is to replace various identification cards. Smart cards will combine paper, plastic and magnetic cards used for identification, automatic teller machines, copiers, toll collection, pay phones, health care and welfare administration. Universities, firms and governments rely on smart identification cards since they can contain more detailed data and enable many services to be integrated. Health care cards, for example, reduce document processing costs by allowing immediate access to personalized patient information stored in smart cards. Most other smart card uses combine identification function with specialized purposes as in military PX cards, government's Electronic Benefit Transfer cards, and university ID cards that are also used to pay for food and photocopies.
14.4 Economic Benefits
Smart cards reduce transaction costs by eliminating paper and paper handling costs in hospitals and government benefit payment programs. Contact and contactless toll payment cards streamline toll collection procedures, reducing labor costs as well as delays caused by manual systems. Maintenance costs for vending machines, petroleum dispensers, parking meters and public phones are lowered while revenues could increase, about 30% in some estimates, due to the convenience of the smart card payment systems in these machines.
14.5 Customization
A smart card contains all the data needed to personalize networking, Web connection, payments and other applications. Using a smart card, one can establish a personalized network connection anywhere in the world using a phone center or an information kiosk. Web servers will verify the user's identity and present a customized Web page, an e-mail connection and other authorized services based on the data read from a smart card. Personal settings for electronic appliances, including computers, will be stored in smart cards rather than in the appliances themselves. Phone numbers are stored in smart cards instead of phones. While appliances become generic tools, users only carry a smart card as the ultimate networking and personal computing device.
14.6 Multifunctionality
The processing power of a smart card makes it ideal to mix multiple functions. For example, government benefit cards will also allow users access to other benefit programs such as health care clinics and job training programs. A college identification card can be used to pay for food, phone calls and photocopies, to access campus networks and to register classes. By integrating many functions, governments and colleges can manage and improve their operations at lower costs and offer innovative services.
Compared to conventional data transmission devices such as magnetic-stripe cards, smart cards offer enhanced security, convenience and economic benefits. In addition, smart card-based systems are highly configurable to suit individual needs. Finally, the multifunctionality as payment, application and networking devices renders a smart card as a perfect user interface in a mobile, networked economy.
14.1. Customer Benefits
14.1.1 Full Portability of Services
The smart card effectively breaks the link between the subscriber and the terminal, allowing the use of any properly equipped terminal and helping to realize the wireless promise of any-time, anywhere communications. In fact, subscribers need not be constrained to using voice terminals only. A variety of other mobile communications devices such as personal digital assistants (PDAs) and personal intelligent communicators (PICs) are available that may have voice communications added as an integral part of their capabilities. If these other devices are equipped for smart cards, the potential for communications is increased. Similarly, data communications applications could benefit from the security features inherent in smart cards.
14.1.2 International Roaming
Wireless customers often require the ability to place and receive calls when traveling abroad. For these customers, international roaming enabled by smart cards is quite valuable. For example, Ameritech, AT&T, and GTE have all instituted international roaming programs using GSM phones and smart cards. The program uses co-branded smart cards, which corporate customers bring with them when they travel abroad. Customers are given a telephone number from a GSM carrier, which allows them to be contacted in any of the countries that have international roaming agreements.
14.1.3 Intersystem Roaming
The incompatibility of different communications radio interfaces and authentication protocols (time division multiple access [TDMA], code division multiple access [CDMA], GSM, personal digital cellular [PDC], mobile satellite systems, etc.) requires subscribers to make choices that constrain them to use only one particular type of handset that works with only one radio interface. With a smart card, it becomes possible for subscribers to use one handset for different interfaces and protocols. This feature is already implemented among the three frequencies used by the GSM platform (900, 1800, and 1900 MHz). American National Standards Institute (ANSI) telephone industry price index (T1P1).3 has recommended standards for a user identity module, a smart card that can be used with the major radio access methods. Thus, it becomes conceivable to have current GSM smart cards modified so that they can work with a CDMA handset. For example, North American GSM operators have designed a process to which the SIM holds both the GSM and advanced mobile phone service (AMPS) authentication algorithm and data to provide authentication on both networks in interroaming situations.
14.1.4 Multiple Services on a Single Card
As mentioned earlier, maximum value is realized by the subscriber when multiple applications are stored on a single card (see Figure). A multiapplication smart card could provide access to airline reservation and ticketing systems and information networks, as well as a mobile telephone service. Considering the many cards that the average person carries these days (i.e., numerous credit cards, debit cards, employee ID cards), integrating more applications into a single card (or at least fewer cards) has obvious appeal and benefits. It is important to note that there is clear interest on the part other industries to package their services with mobile telephony. For example, research by Citibank indicates clearly that a substantial percentage of the company's customers would like to be able to conduct its banking on a variety of platforms, including wireless. Such services are already available using a standardized toolbox for smart-card application creation.
14.1.5 Separation of Business and Personal Calls
The smart card allows customers to be billed separately for personal and business calls made on a single phone. For example, Airtel, a Spanish GSM operator, uses a SIM card with two sets of subscription information—one for corporate and the other for personal use. Airtel’s dual SIM cards have been well received in the corporate market.
14.2 Enhanced Security Benefits
SIM cards have several features that enhance security for wireless communications networks. Smart-card supporters point to the potential of limiting or eliminating fraud as one of their strongest selling points.
SIM cards provide a secure authentication key transport container from the carrier’s authentication center to the end-user’s terminal. Their superior fraud protection is enabled by hosting the cryptographic authentication algorithm and data on the card’s microprocessor chip. SIM cards can be personal identification number (PIN) protected and include additional protection against logical attacks. With added PIN code security, SIM cards offer the same level of security used by banks for securing off-line payments.
Because the home network–authentication algorithm also resides in the card, SIM cards make secure roaming possible. They can also include various authentication mechanisms for internetwork roaming of different types.
Complete fraud protection (with the exclusion of subscription fraud) can only be provided in the context of a complete security framework that includes terminal authentication, an authentication center, and authentication key management. Smart cards are an essential piece of this environment, but only the complete architecture can allow fraud reduction and secure roaming.
Finally, it should be noted that biometric smart-card applications such as voice or fingerprint recognition could be added to provide maximum fraud prevention. Smart cards could then combine the three basic security blocks of possession, knowledge, and characteristics (see Figure ).
14.3 Convenience
One use of the old fashioned memory cards is to replace various identification cards. Smart cards will combine paper, plastic and magnetic cards used for identification, automatic teller machines, copiers, toll collection, pay phones, health care and welfare administration. Universities, firms and governments rely on smart identification cards since they can contain more detailed data and enable many services to be integrated. Health care cards, for example, reduce document processing costs by allowing immediate access to personalized patient information stored in smart cards. Most other smart card uses combine identification function with specialized purposes as in military PX cards, government's Electronic Benefit Transfer cards, and university ID cards that are also used to pay for food and photocopies.
14.4 Economic Benefits
Smart cards reduce transaction costs by eliminating paper and paper handling costs in hospitals and government benefit payment programs. Contact and contactless toll payment cards streamline toll collection procedures, reducing labor costs as well as delays caused by manual systems. Maintenance costs for vending machines, petroleum dispensers, parking meters and public phones are lowered while revenues could increase, about 30% in some estimates, due to the convenience of the smart card payment systems in these machines.
14.5 Customization
A smart card contains all the data needed to personalize networking, Web connection, payments and other applications. Using a smart card, one can establish a personalized network connection anywhere in the world using a phone center or an information kiosk. Web servers will verify the user's identity and present a customized Web page, an e-mail connection and other authorized services based on the data read from a smart card. Personal settings for electronic appliances, including computers, will be stored in smart cards rather than in the appliances themselves. Phone numbers are stored in smart cards instead of phones. While appliances become generic tools, users only carry a smart card as the ultimate networking and personal computing device.
14.6 Multifunctionality
The processing power of a smart card makes it ideal to mix multiple functions. For example, government benefit cards will also allow users access to other benefit programs such as health care clinics and job training programs. A college identification card can be used to pay for food, phone calls and photocopies, to access campus networks and to register classes. By integrating many functions, governments and colleges can manage and improve their operations at lower costs and offer innovative services.
5 smartcard
15 Marketing Opportunities
In addition to the value-added services they can provide, smart cards provide many marketing opportunities to network operators.
15.1 Brand Recognition
Smart cards provide a means for greater brand exposure and reinforcement. The cards can be considered mini-billboards, providing frequent opportunities for the customer to be exposed to a brand name. Compared to other advertising media, they provide a cost-effective vehicle for achieving a high number of brand exposures to a targeted audience. Network operators with limited brand recognition can co-brand their cards with companies with greater brand equity to strengthen their market positions.
15.2 Customer Loyalty Programs
Smart cards can play an extremely valuable role in a carrier’s customer retention efforts. The data on a smart card is a digital representation of the customer’s habits; i.e., number of calls, services accessed, merchandise purchases, etc. This rich database of customer information makes it possible for network operators to develop highly targeted or one-to-one marketing. Carriers are then able to provide services and offerings particularly suited to their customers, increasing customer loyalty to the carrier.
15.3 Direct Marketing
With their convenient form factor, smart cards can be used in direct-mail campaigns to sell wireless subscriptions, both for prospecting and subscription renewal. Using temporary or prepaid smart cards, network operators have a low-cost channel for selling their services. In addition, subscription changes, renewals, and upgrades are easily handled by sending new cards in the mail (see Figure 4).
Figure 4. A Direct Marketing Scenario
15.4 Advertising
Two services, used in conjunction with smart cards, provide network operators with possibilities for highly targeted advertising. Short message service (SMS) and cell broadcast leverage smart cards to send advertising or informational messages that appear on the handset display to wireless users.
15.5 Trial Subscriptions
Smart cards are an ideal vehicle for trial subscriptions. Programmed as prepaid cards, they can attract new customers to try wireless services with limited, defined financial risk for both the network operator and the consumer.
15.5 Incidental Revenues
Network operators issuing smart cards can generate additional revenue by selling memory space on the card to other companies. For example, available space can be sold to gas stations so that the smart card can also be used as a debit card for gas purchases. The card’s surface can also be used for imprinting the participating company’s brand, for which the carrier can receive fees for space advertising.
In addition to the value-added services they can provide, smart cards provide many marketing opportunities to network operators.
15.1 Brand Recognition
Smart cards provide a means for greater brand exposure and reinforcement. The cards can be considered mini-billboards, providing frequent opportunities for the customer to be exposed to a brand name. Compared to other advertising media, they provide a cost-effective vehicle for achieving a high number of brand exposures to a targeted audience. Network operators with limited brand recognition can co-brand their cards with companies with greater brand equity to strengthen their market positions.
15.2 Customer Loyalty Programs
Smart cards can play an extremely valuable role in a carrier’s customer retention efforts. The data on a smart card is a digital representation of the customer’s habits; i.e., number of calls, services accessed, merchandise purchases, etc. This rich database of customer information makes it possible for network operators to develop highly targeted or one-to-one marketing. Carriers are then able to provide services and offerings particularly suited to their customers, increasing customer loyalty to the carrier.
15.3 Direct Marketing
With their convenient form factor, smart cards can be used in direct-mail campaigns to sell wireless subscriptions, both for prospecting and subscription renewal. Using temporary or prepaid smart cards, network operators have a low-cost channel for selling their services. In addition, subscription changes, renewals, and upgrades are easily handled by sending new cards in the mail (see Figure 4).
Figure 4. A Direct Marketing Scenario
15.4 Advertising
Two services, used in conjunction with smart cards, provide network operators with possibilities for highly targeted advertising. Short message service (SMS) and cell broadcast leverage smart cards to send advertising or informational messages that appear on the handset display to wireless users.
15.5 Trial Subscriptions
Smart cards are an ideal vehicle for trial subscriptions. Programmed as prepaid cards, they can attract new customers to try wireless services with limited, defined financial risk for both the network operator and the consumer.
15.5 Incidental Revenues
Network operators issuing smart cards can generate additional revenue by selling memory space on the card to other companies. For example, available space can be sold to gas stations so that the smart card can also be used as a debit card for gas purchases. The card’s surface can also be used for imprinting the participating company’s brand, for which the carrier can receive fees for space advertising.
Sunday, August 15, 2010
Social Networking Website Security Mitigation
Social Networking Website Security Mitigation
The use of social networking site at CDC, such as Facebook and MySpace, increases risk to CDC systems and data via three main mechanisms: 1) Web mail communication, which by-passes enterprise mail filtering, and 2) public comments on blog posts, which are often vulnerable to cross-site scripting (XSS) or blog-phishing attacks, and 3) malicious ‘friends’, whereby those who are accepted as ‘friends’, may change their profiles after being approved to purposely include malicious code, spurious, offensive, inappropriate or political content.
Social networking sites and other Web 2.0 technologies offer health communicators powerful new channels to deliver relevant and targeted health messages, often through trusted sources, when, where and how users want information. Since these technologies are newly emerging and are unfortunately prone to security vulnerabilities and attack vectors, mitigating these risks to protect the CDC network remains paramount to OCISO and the programs alike.
This document aims to outline the steps of risk assessment for individual sites and recommendations for mitigating these known risks when they are present.
OCISO makes two general recommendations1 regarding social networking sites and the first two main vulnerability classes:
Do not use the Web mail portion of these sites.
Disable comments on blogs and other public commenting sections.
OCISO does not offer recommendations regarding the third vulnerability, malicious ‘friends’.
The use of social networking site at CDC, such as Facebook and MySpace, increases risk to CDC systems and data via three main mechanisms: 1) Web mail communication, which by-passes enterprise mail filtering, and 2) public comments on blog posts, which are often vulnerable to cross-site scripting (XSS) or blog-phishing attacks, and 3) malicious ‘friends’, whereby those who are accepted as ‘friends’, may change their profiles after being approved to purposely include malicious code, spurious, offensive, inappropriate or political content.
Social networking sites and other Web 2.0 technologies offer health communicators powerful new channels to deliver relevant and targeted health messages, often through trusted sources, when, where and how users want information. Since these technologies are newly emerging and are unfortunately prone to security vulnerabilities and attack vectors, mitigating these risks to protect the CDC network remains paramount to OCISO and the programs alike.
This document aims to outline the steps of risk assessment for individual sites and recommendations for mitigating these known risks when they are present.
OCISO makes two general recommendations1 regarding social networking sites and the first two main vulnerability classes:
Do not use the Web mail portion of these sites.
Disable comments on blogs and other public commenting sections.
OCISO does not offer recommendations regarding the third vulnerability, malicious ‘friends’.
Web Mail:
Web Mail:
Most functions of social networking sites are usually available even when Web mail is not used or blocked by Websense. When possible, this is the recommended route, not only in terms of security, but also convenience. If possible, have incoming mail automatically redirected to a specific, group CDC account, since it would allow the regular enterprise mail filters to scan the incoming mail traffic.
If Web mail is required to effectively use the site, then a computer off the CDC network will have to be used to manage and maintain the site. This requires separate hardware and connection to the Internet.
Most functions of social networking sites are usually available even when Web mail is not used or blocked by Websense. When possible, this is the recommended route, not only in terms of security, but also convenience. If possible, have incoming mail automatically redirected to a specific, group CDC account, since it would allow the regular enterprise mail filters to scan the incoming mail traffic.
If Web mail is required to effectively use the site, then a computer off the CDC network will have to be used to manage and maintain the site. This requires separate hardware and connection to the Internet.
Public Comments:
Public Comments:
OCISO recommends that comments be disabled. Even moderated comments pose a risk to the CDC network, since each of the comments have to be opened and evaluated by someone on a CDC network computer. There is no way to moderate the comments without the moderator’s system being in jeopardy. However, not allowing comments on blog posts and other content not only is contrary to the very nature of these peer-to-peer communications platforms and thereby reducing the site’s effectiveness, often a negative backlash is encountered, which undermines the effectiveness of our communications efforts.
From a communications perspective, we recommend allowing comments, but having all comments moderated. A special computer off the CDC network will be required to manage and maintain the site. This necessitates the purchase of separate hardware and connection to the Internet.
OCISO recommends that comments be disabled. Even moderated comments pose a risk to the CDC network, since each of the comments have to be opened and evaluated by someone on a CDC network computer. There is no way to moderate the comments without the moderator’s system being in jeopardy. However, not allowing comments on blog posts and other content not only is contrary to the very nature of these peer-to-peer communications platforms and thereby reducing the site’s effectiveness, often a negative backlash is encountered, which undermines the effectiveness of our communications efforts.
From a communications perspective, we recommend allowing comments, but having all comments moderated. A special computer off the CDC network will be required to manage and maintain the site. This necessitates the purchase of separate hardware and connection to the Internet.
Malicious ‘Friends’:
Malicious ‘Friends’:
Once friends are approved on a social networking profile, vigilance is required to make sure that the friend’s profile hasn’t changed to include inappropriate content, an inappropriate profile image or malicious code. The simple act of reviewing proposed friends may make the administrator’s system vulnerable to attack. Although most users of such social networking site already understand this, disclaimers about friends and content on their profiles should be posted. Clear policies about accepting friends should be posted as well. Some sites such as MySpace allow you to control which friends get listed on your main profile page, whereas others such as Facebook randomly place any of your friends on the main page, in which case, care must be taken in approving friends.
This vulnerability is the same as attacks whereby developers work to get a site high in Google or other search engine results, and then changing the content of their pages to purposely introduce attacks.
Again, the main recommendation is to use computer resources off the CDC network to manage and maintain the profile. This requires separate hardware and connection to the Internet.
Once friends are approved on a social networking profile, vigilance is required to make sure that the friend’s profile hasn’t changed to include inappropriate content, an inappropriate profile image or malicious code. The simple act of reviewing proposed friends may make the administrator’s system vulnerable to attack. Although most users of such social networking site already understand this, disclaimers about friends and content on their profiles should be posted. Clear policies about accepting friends should be posted as well. Some sites such as MySpace allow you to control which friends get listed on your main profile page, whereas others such as Facebook randomly place any of your friends on the main page, in which case, care must be taken in approving friends.
This vulnerability is the same as attacks whereby developers work to get a site high in Google or other search engine results, and then changing the content of their pages to purposely introduce attacks.
Again, the main recommendation is to use computer resources off the CDC network to manage and maintain the profile. This requires separate hardware and connection to the Internet.
Primary recommendations:
Primary recommendations:
Since most Web 2.0 technologies are still emerging and secure coding practices are not industry-wide, it is recommended to do a risk assessment for each social networking, Web 2.0 community you wish to use for official CDC communications to determine whether Web mail and public comments are allowed and are necessary. Most times they are either required or greatly preferred, and in those cases the only way to currently protect the CDC network is to manage and maintain these sites on hardware off the CDC network.
Programs must work with OCISO to develop appropriate Rules of Behavior (ROB) for those who will use the special hardware to manage these profiles. These ROB will include provisions of not connecting the hardware to the CDC network, trying to reenable ports if OCISO has blocked them, or moving files from the system to the network directly in any way. Special connections to the Internet must be acquired, which is usually a wireless Internet card. If DSL, cable or T1 connections are required, then the program must also include ITSO in on the discussions at an early stage.
Programs should develop a system to regularly and systematically review the URLs in any comment for XSS on the destination. Those who do the scanning and review should be trained on how to look for suspicious XSS type of code in a page. The use of automated tools are generally restricted by license agreements.
Programs should also develop a system to regularly and systematically review the profile pages of friends as well, to ensure that content has not changed since initial acceptance and that those profiles have not been compromised.
Programs should also routinely scan the security environment and vulnerabilities databases to stay breast of the changing security landscape associated with these sites.
Since most Web 2.0 technologies are still emerging and secure coding practices are not industry-wide, it is recommended to do a risk assessment for each social networking, Web 2.0 community you wish to use for official CDC communications to determine whether Web mail and public comments are allowed and are necessary. Most times they are either required or greatly preferred, and in those cases the only way to currently protect the CDC network is to manage and maintain these sites on hardware off the CDC network.
Programs must work with OCISO to develop appropriate Rules of Behavior (ROB) for those who will use the special hardware to manage these profiles. These ROB will include provisions of not connecting the hardware to the CDC network, trying to reenable ports if OCISO has blocked them, or moving files from the system to the network directly in any way. Special connections to the Internet must be acquired, which is usually a wireless Internet card. If DSL, cable or T1 connections are required, then the program must also include ITSO in on the discussions at an early stage.
Programs should develop a system to regularly and systematically review the URLs in any comment for XSS on the destination. Those who do the scanning and review should be trained on how to look for suspicious XSS type of code in a page. The use of automated tools are generally restricted by license agreements.
Programs should also develop a system to regularly and systematically review the profile pages of friends as well, to ensure that content has not changed since initial acceptance and that those profiles have not been compromised.
Programs should also routinely scan the security environment and vulnerabilities databases to stay breast of the changing security landscape associated with these sites.
System Definition and Boundaries:
System Definition and Boundaries:
Until these sites can be made more secure across the board, it is not recommended at this time to treat the information published to these systems as information of record or official. Disclaimers should be made on the profiles of each of these sites to state that official CDC information can be found at CDC.gov and that in the case of any discrepancies that the content on CDC.gov be considered correct. Even though clear system boundaries are established, programs participating in the spaces must assume the risk that content may be subject to attack and change, since ITSO and OCISO do not maintain these systems.
It is not recommended to use these social networks to gather personal information or to be used for private or secure communications.
Until these sites can be made more secure across the board, it is not recommended at this time to treat the information published to these systems as information of record or official. Disclaimers should be made on the profiles of each of these sites to state that official CDC information can be found at CDC.gov and that in the case of any discrepancies that the content on CDC.gov be considered correct. Even though clear system boundaries are established, programs participating in the spaces must assume the risk that content may be subject to attack and change, since ITSO and OCISO do not maintain these systems.
It is not recommended to use these social networks to gather personal information or to be used for private or secure communications.
Social Networks Site Analyses:
Social Networks Site Analyses:
MySpace: Since this site relies on Web mail to solicit and accept friends and the blog moderating functions have been known to have XSS vulnerabilities in the past, it is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Facebook: Since this site allows blog posts and there is limited or no control over which of your friends appear on your home page, it is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Twitter: An interesting site in terms of social networking in that comments and posts are allowed, but are limited to 140 characters with no HTML or JS allowed. Hyperlinks are allowed and are automatically converted to the actual HTML code by the system. Eg – http://www.cdc.gov becomes http://www.cdc.gov automatically. Comments are designed to be sent by SMS messaging, which is text based. Requests for followers come through email and can be accepted without Web mail. Whereas it does seem to be secure against XSS exploits, the site does rely on AJAX technologies and can be used to post links to malicious sites. In order to vet these links, they must be followed, which would put the system at risk. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
DailyStrength: This site relies on Web mail to solicit and accept friends, allows blog comments and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
YouTube: This site allows comments on videos and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Flickr: This site allows comments and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
MySpace: Since this site relies on Web mail to solicit and accept friends and the blog moderating functions have been known to have XSS vulnerabilities in the past, it is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Facebook: Since this site allows blog posts and there is limited or no control over which of your friends appear on your home page, it is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Twitter: An interesting site in terms of social networking in that comments and posts are allowed, but are limited to 140 characters with no HTML or JS allowed. Hyperlinks are allowed and are automatically converted to the actual HTML code by the system. Eg – http://www.cdc.gov becomes http://www.cdc.gov automatically. Comments are designed to be sent by SMS messaging, which is text based. Requests for followers come through email and can be accepted without Web mail. Whereas it does seem to be secure against XSS exploits, the site does rely on AJAX technologies and can be used to post links to malicious sites. In order to vet these links, they must be followed, which would put the system at risk. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
DailyStrength: This site relies on Web mail to solicit and accept friends, allows blog comments and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
YouTube: This site allows comments on videos and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Flickr: This site allows comments and has limited to no control over which of your friends show up on your main profile page. It is recommended that to use this site for CDC communications, it be done so from specially designated hardware off the CDC network following guidelines developed in conjunction with OCISO.
Wednesday, August 11, 2010
CALL FORGING:
CALL FORGING:
Caller ID Forging the practice of causing the telephone network to display a number on the recipient's caller ID display which is not that of the actual originating station; the term is commonly used to describe situations in which the motivation is considered nefarious by the speaker. Just as e-mail spoofing can make it appear that a message came from any e-mail address the sender chooses, caller ID forging can make a call appear to have come from any phone number the caller wishes. Because people are prone to assume a call is coming from the number (and hence, the associated person, or persons), this can call the service's value into question.
To use a typical service, a customer pays in advance for a PIN allowing them to make a call for a certain amount of minutes. To begin, the customer dials from any phone the toll free number given to them by the company and enters their PIN. They are then asked to enter the number they wish to call and the number they wish to appear on the caller ID. Once the "customer" selects the options, the call is then bridged and the person on the other end assumes someone else is calling them.
Many Caller ID forging service providers also allow customers to initiate spoofed calls from a web-based interface in addition to calling a toll free number and entering the ten digit number you want to display followed by the ten digit number you want to call. Some providers allow you to enter the name you would like to display along with the spoofed Caller ID number but in most parts of the United States for example, whatever name the local phone company has associated with the spoofed Caller ID number is the name that shows up on the Caller ID display.
Using a web-based spoofing form involves creating an account with a provider, logging in to their website and completing a form. Most companies require the following basic fields:
1: Source number 2: Destination number 3: Caller ID number
Once the user completes this form and clicks a button to initiate the call, the source number is first called. Once the source number line is picked up, the destination is then called and bridged together.
Some providers also offer the ability to record calls, change your voice and send SMS text messages.
Methods:
Caller ID is forged through a variety of methods and different technology. The most popular ways of spoofing Caller ID are through the use of Voice over IP or PRI lines.
Another method of spoofing is that of emulating the Bell 202 FSK signal. This method, informally called orange boxing, uses software that generates the audio signal which is then coupled to the telephone line during the call. The object is to deceive the called party into thinking that there is an incoming call waiting call from the spoofed number, when in fact there is no new incoming call. This technique often also involves an accomplice who may provide a secondary voice to complete the illusion of a call waiting call. Because the orange box cannot truly spoof incoming caller ID prior to answer, and relies to a certain extent on the guile of the caller, it is considered as much a social engineering technique as a technical hack.
Other methods include switch access to the SS7 network, and social engineering telephone company operators into placing calls for you from the desired phone number. Another method that is not used as often is VXML which was gaining popularity before VoIP took over.
History:
Many people do not realize that Caller ID Forging has been around since Caller ID was created. For over a decade Caller ID forging was used mainly by businesses with access to expensive PRI (Primary Rate Interface) telephone lines provided by local telephone carriers. A single PRI line can provided businesses with up to 23 telephone lines and all of these lines are capable of having unique telephone numbers. Caller ID forging, in it’s most basic form, was typically used by businesses to display one main telephone number on all outgoing calls, even though those calls were not really originating from those numbers.
In the early 2000’s phone hackers, also known as “phone phreaks” or “phreaks”, began using Orange boxing to attempt to spoof Caller ID. Orange boxing is done by using a device, usually special computer software, to send a series of tones down the line during the first few seconds of a phone call, attempting to emulate the Caller ID signal sent from the telephone office. Orange boxing is very crude and unreliable, as it has to be done within a short timeframe at the beginning of a call. Phone phreaks, without access to PRI lines or blind line services at the time, thought the technique was clever.
In late 2003 and early 2004 the same phone phreaks began to explore a relatively new platform for developing voice applications, known as VoiceXML or VXML, which was offered by companies such as Voxeo.
In 2005 a handful of new sites allowing you to spoof your Caller ID were quietly launched. Some of the sites were PiPhone.com, CallNotes.net, SecretCalls.net, StayUnknown.com, SpoofTech.com, SpoofTel.com, and SpoofCard.com.
Towards the end of May, another site, TheZeroGroup.com, launched offering Caller ID spoofing, amongst it's other phone related services. TheZeroGroup's site claims they are hosted off-shore to avoid any legal issues that may arise.
On June 13th the U.S. House of Representatives passed the "Truth in Caller ID Act of 2007" which would make it "unlawful for any person within the United States, in connection with any telecommunications service or VOIP service, to cause any caller identification service to transmit misleading or inaccurate caller identification information with the intent to defraud or cause harm." A similiar bill was passed onto the Senate in April, but the Senate hasn't acted on either of the bills yet.
In India,we do not have any law which is related to the crime made by hoaxters by spoofing caller id.
Orkut Server Side Session Handling Problems:
Overview:
1. Orkut fails to expire the orkut_state session cookie from the server side even when the
user logs off from Orkut upon clicking "Sign-Out" from the application. The cookie is
cleared from the client side (browser), but is not cleared from the server side. If reused,
it provides access to the user's Orkut account.
2. Upon logging in again, a new orkut_state session cookie is created, but the old session
cookies still stay active on the server side. Therefore, any session cookie can be reused
to gain access to the user's Orkut account.
Details:
When any user logs into “orkut.com” . data of cookie will be generated on server and it will be sent back to user after successful authentication process on server. If I come to know about cookie data of any victim remotely then I can access victim’s account without password ( and even user id).
After an access to victim's account, I can edit his/her social,personal,professional,contact profiles,i can also have an access to his/her albums,videos,testimonials.i can even stop victim to access his/her account by editing the contact email.
My aim is not to hack the orkut account and damaged any victim's data, but to create awareness among the people about the security risks over social networking websites.
Recently I had been interviewed by HEADLINES TODAY and I have proved live that any orkut account can be hacked. I am also going to do half an hour live show on AAJTAK.
More Details will be covered in LIVE demonstration.
Gmail Server Side Session Handling Problems:
Overview:
1. Gmail fails to expire the GX session cookie from the server side even when the user
logs off from Gmail upon clicking "Sign-Out" from the application. The cookie is
cleared from the client side (browser), but is not cleared from the server side. If reused,
it provides access to the user's Gmail account.
2. Upon logging in again, a new GX session cookie is created, but the old session cookies
still stay active on the server side. Therefore, any session cookie can be re-used to
gain access to the user's Gmail account
More details will be covered in LIVE Demostration.
plz contect +919766928955
Caller ID Forging the practice of causing the telephone network to display a number on the recipient's caller ID display which is not that of the actual originating station; the term is commonly used to describe situations in which the motivation is considered nefarious by the speaker. Just as e-mail spoofing can make it appear that a message came from any e-mail address the sender chooses, caller ID forging can make a call appear to have come from any phone number the caller wishes. Because people are prone to assume a call is coming from the number (and hence, the associated person, or persons), this can call the service's value into question.
To use a typical service, a customer pays in advance for a PIN allowing them to make a call for a certain amount of minutes. To begin, the customer dials from any phone the toll free number given to them by the company and enters their PIN. They are then asked to enter the number they wish to call and the number they wish to appear on the caller ID. Once the "customer" selects the options, the call is then bridged and the person on the other end assumes someone else is calling them.
Many Caller ID forging service providers also allow customers to initiate spoofed calls from a web-based interface in addition to calling a toll free number and entering the ten digit number you want to display followed by the ten digit number you want to call. Some providers allow you to enter the name you would like to display along with the spoofed Caller ID number but in most parts of the United States for example, whatever name the local phone company has associated with the spoofed Caller ID number is the name that shows up on the Caller ID display.
Using a web-based spoofing form involves creating an account with a provider, logging in to their website and completing a form. Most companies require the following basic fields:
1: Source number 2: Destination number 3: Caller ID number
Once the user completes this form and clicks a button to initiate the call, the source number is first called. Once the source number line is picked up, the destination is then called and bridged together.
Some providers also offer the ability to record calls, change your voice and send SMS text messages.
Methods:
Caller ID is forged through a variety of methods and different technology. The most popular ways of spoofing Caller ID are through the use of Voice over IP or PRI lines.
Another method of spoofing is that of emulating the Bell 202 FSK signal. This method, informally called orange boxing, uses software that generates the audio signal which is then coupled to the telephone line during the call. The object is to deceive the called party into thinking that there is an incoming call waiting call from the spoofed number, when in fact there is no new incoming call. This technique often also involves an accomplice who may provide a secondary voice to complete the illusion of a call waiting call. Because the orange box cannot truly spoof incoming caller ID prior to answer, and relies to a certain extent on the guile of the caller, it is considered as much a social engineering technique as a technical hack.
Other methods include switch access to the SS7 network, and social engineering telephone company operators into placing calls for you from the desired phone number. Another method that is not used as often is VXML which was gaining popularity before VoIP took over.
History:
Many people do not realize that Caller ID Forging has been around since Caller ID was created. For over a decade Caller ID forging was used mainly by businesses with access to expensive PRI (Primary Rate Interface) telephone lines provided by local telephone carriers. A single PRI line can provided businesses with up to 23 telephone lines and all of these lines are capable of having unique telephone numbers. Caller ID forging, in it’s most basic form, was typically used by businesses to display one main telephone number on all outgoing calls, even though those calls were not really originating from those numbers.
In the early 2000’s phone hackers, also known as “phone phreaks” or “phreaks”, began using Orange boxing to attempt to spoof Caller ID. Orange boxing is done by using a device, usually special computer software, to send a series of tones down the line during the first few seconds of a phone call, attempting to emulate the Caller ID signal sent from the telephone office. Orange boxing is very crude and unreliable, as it has to be done within a short timeframe at the beginning of a call. Phone phreaks, without access to PRI lines or blind line services at the time, thought the technique was clever.
In late 2003 and early 2004 the same phone phreaks began to explore a relatively new platform for developing voice applications, known as VoiceXML or VXML, which was offered by companies such as Voxeo.
In 2005 a handful of new sites allowing you to spoof your Caller ID were quietly launched. Some of the sites were PiPhone.com, CallNotes.net, SecretCalls.net, StayUnknown.com, SpoofTech.com, SpoofTel.com, and SpoofCard.com.
Towards the end of May, another site, TheZeroGroup.com, launched offering Caller ID spoofing, amongst it's other phone related services. TheZeroGroup's site claims they are hosted off-shore to avoid any legal issues that may arise.
On June 13th the U.S. House of Representatives passed the "Truth in Caller ID Act of 2007" which would make it "unlawful for any person within the United States, in connection with any telecommunications service or VOIP service, to cause any caller identification service to transmit misleading or inaccurate caller identification information with the intent to defraud or cause harm." A similiar bill was passed onto the Senate in April, but the Senate hasn't acted on either of the bills yet.
In India,we do not have any law which is related to the crime made by hoaxters by spoofing caller id.
Orkut Server Side Session Handling Problems:
Overview:
1. Orkut fails to expire the orkut_state session cookie from the server side even when the
user logs off from Orkut upon clicking "Sign-Out" from the application. The cookie is
cleared from the client side (browser), but is not cleared from the server side. If reused,
it provides access to the user's Orkut account.
2. Upon logging in again, a new orkut_state session cookie is created, but the old session
cookies still stay active on the server side. Therefore, any session cookie can be reused
to gain access to the user's Orkut account.
Details:
When any user logs into “orkut.com” . data of cookie will be generated on server and it will be sent back to user after successful authentication process on server. If I come to know about cookie data of any victim remotely then I can access victim’s account without password ( and even user id).
After an access to victim's account, I can edit his/her social,personal,professional,contact profiles,i can also have an access to his/her albums,videos,testimonials.i can even stop victim to access his/her account by editing the contact email.
My aim is not to hack the orkut account and damaged any victim's data, but to create awareness among the people about the security risks over social networking websites.
Recently I had been interviewed by HEADLINES TODAY and I have proved live that any orkut account can be hacked. I am also going to do half an hour live show on AAJTAK.
More Details will be covered in LIVE demonstration.
Gmail Server Side Session Handling Problems:
Overview:
1. Gmail fails to expire the GX session cookie from the server side even when the user
logs off from Gmail upon clicking "Sign-Out" from the application. The cookie is
cleared from the client side (browser), but is not cleared from the server side. If reused,
it provides access to the user's Gmail account.
2. Upon logging in again, a new GX session cookie is created, but the old session cookies
still stay active on the server side. Therefore, any session cookie can be re-used to
gain access to the user's Gmail account
More details will be covered in LIVE Demostration.
plz contect +919766928955
SMS FORGING:
SMS FORGING:
SMS forging is a relatively new kind of high-tech felony, which uses the short message service (SMS), which is available on most mobile phones and personal digital assistants, to spoof or impersonate another user. The spoofing is often used to send viruses that can be carried from phone to phone and which can cause destructive behavior.
SMS spoofing became possible after many mobile/cellular operators had integrated their network communications with/in the Internet. So anybody could send SMS from the Internet using forms at the websites of mobile operators or even through e-mail. Unfortunately, the Internet forms designed to send SMS may have vulnerabilities that could lead hackers to be able to break the tunneling protocol that links the phones with the Internet.
Surprisingly, one can use legitimate SMS tools available on the market for spoofing. For instance, Clickatell, a provider of carrier-grade bulk SMS messaging solutions and applications that can be integrated and used immediately within a global environment, developed various software allowing users to send bulk and personalized SMS messaging to existing databases, Lotus Domino and other integrated SMS solutions. Therefore any person can purchase or even download evaluation software that would allow the individual to send a spoof SMS. Other providers such as FakeMyText and CloakText actually sell an anonymous texting service as their main service which can be used to spoof a SMS message from any international number.
There is also dedicated Open Source tool called SMS Spoof, which is a Palm OS application that allows individuals to send spoofed SMS messages. It uses a dialup connection to any EMI/UCP-compatible short message service center (SMSC) which supports the EMI/UCP protocol, as long as no authentication is required.
Details:
Every SMS sent from sender to receiver is in PDU format which is of 7bit .
07917283010010F5040BC87238880900F10000993092516195800AE8329BFD4697D9
Octet(s)Description:-
07Length of the SMSC information (in this case 7 octets)
91Type-of-address of the SMSC. (91 means international format of the phone number)
72 83 01 00 10 F5Service center number(in decimal semi-octets). The length of the phone number is odd (11), so a trailing F has been added to form proper octets. The phone number of this service center is "+27381000015".
04First octet of this SMS-DELIVER message .
0BAddress-Length. Length of the sender number (0B hex = 11 dec)
C8Type-of-address of the sender number
72 38 88 09 00 F1Sender number (decimal semi-octets), with a trailing F, By changing this format at the sender side,we can spoof sender ID of the SMS.
SMS forging is a relatively new kind of high-tech felony, which uses the short message service (SMS), which is available on most mobile phones and personal digital assistants, to spoof or impersonate another user. The spoofing is often used to send viruses that can be carried from phone to phone and which can cause destructive behavior.
SMS spoofing became possible after many mobile/cellular operators had integrated their network communications with/in the Internet. So anybody could send SMS from the Internet using forms at the websites of mobile operators or even through e-mail. Unfortunately, the Internet forms designed to send SMS may have vulnerabilities that could lead hackers to be able to break the tunneling protocol that links the phones with the Internet.
Surprisingly, one can use legitimate SMS tools available on the market for spoofing. For instance, Clickatell, a provider of carrier-grade bulk SMS messaging solutions and applications that can be integrated and used immediately within a global environment, developed various software allowing users to send bulk and personalized SMS messaging to existing databases, Lotus Domino and other integrated SMS solutions. Therefore any person can purchase or even download evaluation software that would allow the individual to send a spoof SMS. Other providers such as FakeMyText and CloakText actually sell an anonymous texting service as their main service which can be used to spoof a SMS message from any international number.
There is also dedicated Open Source tool called SMS Spoof, which is a Palm OS application that allows individuals to send spoofed SMS messages. It uses a dialup connection to any EMI/UCP-compatible short message service center (SMSC) which supports the EMI/UCP protocol, as long as no authentication is required.
Details:
Every SMS sent from sender to receiver is in PDU format which is of 7bit .
07917283010010F5040BC87238880900F10000993092516195800AE8329BFD4697D9
Octet(s)Description:-
07Length of the SMSC information (in this case 7 octets)
91Type-of-address of the SMSC. (91 means international format of the phone number)
72 83 01 00 10 F5Service center number(in decimal semi-octets). The length of the phone number is odd (11), so a trailing F has been added to form proper octets. The phone number of this service center is "+27381000015".
04First octet of this SMS-DELIVER message .
0BAddress-Length. Length of the sender number (0B hex = 11 dec)
C8Type-of-address of the sender number
72 38 88 09 00 F1Sender number (decimal semi-octets), with a trailing F, By changing this format at the sender side,we can spoof sender ID of the SMS.
Saturday, August 7, 2010
Conclusion
Conclusion
Plasma Display Panel is today’s technology that had made human dream come true. Altogether Future world will be the one which will make human happiest living being on earth.
Plasma Display Panel is today’s technology that had made human dream come true. Altogether Future world will be the one which will make human happiest living being on earth.
Advantages & Disadvantages
Advantages & Disadvantages
• Advantages
• Slim profile
• Can be wall mounted
• Lighter and less bulky than rear-projection televisions
• Achieves better and more accurate color reproduction than LCDs (68 billion/236 versus 16.7 million/224)
• Produces deep, true blacks allowing for superior contrast ratios (up to 1:2,000,000)
• Far wider viewing angles than those of LCD (up to 178°); images do not suffer from degradation at high angles unlike LCDs
• Virtually no motion blur, thanks in large part to very high refresh rates and a faster response time, contributing to superior performance when displaying content with significant amounts of rapid motion
• Disadvantages
• Earlier models are susceptible to screen burn-in and image retention (however, newer models have green phosphors and built-in technologies to eliminate this, such as pixel shifting)
• Phosphors in older models lose luminosity over time, resulting in gradual decline of absolute image brightness (newer models are less susceptible to this, having life spans exceeding 60,000 hours, far longer than older CRT technology)
• Susceptible to "large area flicker"
• Generally do not come in smaller sizes than 32 inches
• Susceptible to reflection glare in bright rooms
• Heavier than LCD due to the requirement of a glass screen to hold the gases
• Use more electricity, on average, than an LCD TV
• Do not work as well at high altitudes due to pressure differential between the gases inside the screen and the air pressure at altitude. It may cause a buzzing noise. Manufacturers rate their screens to indicate the altitude parameters.
• For those who wish to listen to AM radio, or are Amateur Radio operators (Hams) or Shortwave Listeners (SWL) , the Radio Frequency Interference (RFI) from these devices can be irritating or disabling.
• Advantages
• Slim profile
• Can be wall mounted
• Lighter and less bulky than rear-projection televisions
• Achieves better and more accurate color reproduction than LCDs (68 billion/236 versus 16.7 million/224)
• Produces deep, true blacks allowing for superior contrast ratios (up to 1:2,000,000)
• Far wider viewing angles than those of LCD (up to 178°); images do not suffer from degradation at high angles unlike LCDs
• Virtually no motion blur, thanks in large part to very high refresh rates and a faster response time, contributing to superior performance when displaying content with significant amounts of rapid motion
• Disadvantages
• Earlier models are susceptible to screen burn-in and image retention (however, newer models have green phosphors and built-in technologies to eliminate this, such as pixel shifting)
• Phosphors in older models lose luminosity over time, resulting in gradual decline of absolute image brightness (newer models are less susceptible to this, having life spans exceeding 60,000 hours, far longer than older CRT technology)
• Susceptible to "large area flicker"
• Generally do not come in smaller sizes than 32 inches
• Susceptible to reflection glare in bright rooms
• Heavier than LCD due to the requirement of a glass screen to hold the gases
• Use more electricity, on average, than an LCD TV
• Do not work as well at high altitudes due to pressure differential between the gases inside the screen and the air pressure at altitude. It may cause a buzzing noise. Manufacturers rate their screens to indicate the altitude parameters.
• For those who wish to listen to AM radio, or are Amateur Radio operators (Hams) or Shortwave Listeners (SWL) , the Radio Frequency Interference (RFI) from these devices can be irritating or disabling.
Plasma Display Manufacturers
Plasma Display Manufacturers
• Panasonic Corporation (formerly Matsushita)
• Samsung Electronics
• LG Electronics
• ProScan
• Fujitsu
• Sanyo
• Funai
• Panasonic Corporation (formerly Matsushita)
• Samsung Electronics
• LG Electronics
• ProScan
• Fujitsu
• Sanyo
• Funai
History
History
Plasma displays were first used in PLATO computer terminals. This PLATO V model illustrates the display's monochromatic orange glow as seen in 1981. The monochrome plasma video display was co-invented in 1964 at the University of Illinois at Urbana-Champaign by Donald Bitzer, H. Gene Slottow, and graduate student Robert Willson for the PLATO Computer System. The original neon orange monochrome Digivue display panels built by glass producer Owens-Illinois were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images. A long period of sales decline occurred in the late 1970s because semiconductor memory made CRT displays cheaper than the US$2500 512 x 512 PLATO plasma displays. Nonetheless, the plasma displays' relatively large screen size and 1 inch thickness made them suitable for high-profile placement in lobbies and stock exchanges.
Electrical engineering student Larry F. Weber became interested in plasma displays while studying at the University of Illinois at Urbana-Champaign in the 1960s, and pursued postgraduate work in the field under Bitzer and Slottow. His research eventually earned him 15 patents relating to plasma displays. One of his early contributions was development of the power-saving "energy recovery sustain circuit", now included in every color plasma display.
Burroughs Corporation, a maker of adding machines and computers, developed the Panaplex display in the early 1970s. The Panaplex display, generically referred to as a gas-discharge or gas-plasma display, uses the same technology as later plasma video displays, but began life as seven-segment display for use in adding machines. They became popular for their bright orange luminous look and found nearly ubiquitous use in cash registers, calculators, pinball machines, aircraft avionics such as radios, navigational instruments, and stormscopes; test equipment such as frequency counters and multimeters; and generally anything that previously used nixie tube or numitron displays with a high digit-count throughout the late 1970s and into the 1990s. These displays remained popular until LEDs gained popularity because of their low-current draw and module-flexibility, but are still found in some applications where their high-brightness is desired, such as pinball machines and avionics. Pinball displays started with six- and seven-digit seven-segment displays and later evolved into 16-digit alphanumeric displays, and later into 128x32 dot-matrix displays in 1990, which are still used today.
1983
In 1983, IBM introduced a 19-inch (48 cm) orange-on-black monochrome display (model 3290 'information panel') which was able to show up to four simultaneous IBM 3270 terminal sessions. Due to heavy competition from monochrome LCD's, in 1987 IBM planned to shut down its factory in upstate New York, the largest plasma plant in the world, in favor of manufacturing mainframe computers.[38] Consequently, Larry Weber co-founded a startup company Plasmaco with Stephen Globus, as well as James Kehoe, who was the IBM plant manager, and bought the plant from IBM. Weber stayed in Urbana as CTO until 1990, then moved to upstate New York to work at Plasmaco.
1992
In 1992, Fujitsu introduced the world's first 21-inch (53 cm) full-color display. It was a hybrid, the plasma display created at the University of Illinois at Urbana-Champaign and NHK STRL.
1994
In 1994, Weber demonstrated color plasma technology at an industry convention in San Jose. Panasonic Corporation began a joint development project with Plasmaco, which led in 1996 to the purchase of Plasmaco, its color AC technology, and its American factory.
1997
In 1997, Fujitsu introduced the first 42-inch (107 cm) plasma display; it had 852x480 resolution and was progressively scanned. Also in 1997, Philips introduced a 42-inch (107 cm) display, with 852x480 resolution. It was the only plasma to be displayed to the retail public in 4Sears locations in the US. The price was US$14,999 and included in-home installation. Later in 1997, Pioneer started selling their first plasma television to the public.
2010 - Present
In late 2006, analysts noted that LCDs overtook plasmas, particularly in the 40-inch (1.0 m) and above segment where plasma had previously gained market share. Another industry trend is the consolidation of manufacturers of plasma displays, with around fifty brands available but only five manufacturers. In the first quarter of 2008 a comparison of worldwide TV sales breaks down to 22.1 million for direct-view CRT, 21.1 million for LCD, 2.8 million for Plasma, and 0.1 million for rear-projection.
Until the early 2000s, plasma displays were the most popular choice for HDTV flat panel display as they had many benefits over LCDs. As well as superior brightness, faster response time, greater color spectrum, and wider viewing angle; they were also much bigger than LCDs, and it was believed that LCD technology was suited only to smaller sized televisions. However, improvements in VLSI fabrication technology have since narrowed the technological gap. The increased size, lower weight, falling prices, and often lower electrical power consumption of LCDs now make them competitive with plasma television sets.
Screen sizes have increased since the introduction of plasma displays. The largest plasma video display in the world at the 2008 Consumer Electronics Show in Las Vegas, Nevada, U.S., North America was a 150-inch (381 cm) unit manufactured by Matsushita Electrical Industries (Panasonic) standing 6 ft (180 cm) tall by 11 ft (330 cm) wide. At the 2010 Consumer Electronics Show in Las Vegas, Nevada, U.S.,North America Panasonic introduced their 152" 2160p 3D plasma.
The plasma video display was co-invented in 1964 at the University of Illinois at Urbana-Champaign by Donald Bitzer, H. Gene Slottow, and graduate student Robert Willson for the PLATO Computer System. The original monochrome (orange, green, yellow) video display panels were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images. This was followed by a long period of sales decline in the late 1970s, as semiconductor memory made CRT displays cheaper than plasma displays. Nonetheless, the relatively large screen size and thin body of plasma displays made them suitable for high-profile placement in lobbies and stock exchanges.
In 1983, IBM introduced a 19-inch (48-cm) orange-on-black monochrome display (model 3290 'information panel'), which was able to show four simultaneous IBM 3270 virtual machine (VM) terminal sessions. That factory was transferred in 1987 to startup company Plasmaco,[1] which was founded by Dr. Larry F. Weber (one of Dr. Bitzer's students) with Stephen Globus and James Kehoe (who was the IBM plant manager).
In 1992, Fujitsu introduced the world's first 21-inch (53-cm) full-color display. It was a hybrid, based on the plasma display created at the University of Illinois at Urbana-Champaign and the Science & Technical Research Laboratories (STRL) of Japan Broadcasting Corporation (NHK), achieving superior brightness.
In 1996, Matsushita Electrical Industries (Panasonic) purchased Plasmaco, its color AC technology, and its American factory. In 1997, Fujitsu introduced the first 42-inch (107-cm) plasma display. It had a resolution of 852x480 and was progressively scanned.[2] Also in 1997, Pioneer started selling the first plasma television to the public. Many current plasma televisions, thinner and of larger area than their predecessors, are in use. Their thin size allows them to compete with large projection screens.
Since then, plasma displays have become thinner and larger in screen size. The largest plasma video display in the world at the 2008 Consumer Electronics Show in Las Vegas, Nevada, USA, was a 150-inch (381 cm) unit manufactured by Matsushita Electrical Industries (Panasonic) standing six ft (180 cm) tall by 11 ft (330 cm) wide and expected to initially retail at US$150,000.[3][4]
Until quite recently, the superior brightness, faster response time, greater color spectrum, and wider viewing angle of color plasma video displays, when compared with LCD (liquid crystal display) televisions, made them one of the most popular forms of display for HDTV (high-definition television) flat panel displays. For a long time, it was widely believed that LCD technology was suited only for smaller sized televisions and could not compete with plasma technology at larger sizes, particularly 40 inches (100 cm) and above. Since then, improvements in LCD technology have narrowed the technological gap. The lower weight, falling prices, higher available resolution (important for HDTV), and often lower electrical power consumption of LCDs make them competitive with plasma television sets. In late 2006, analysts noted that LCDs were overtaking plasmas, particularly in the important 40-inch (1.0 m) and above segment, where plasmas had previously enjoyed strong dominance.
The industry has also been trending toward the consolidation of manufacturers of plasma displays, with around fifty brands available but only five manufacturers. In the first quarter of 2008, a comparison of worldwide TV sales broke down to 22.1 million for CRT, 21.1 million for LCD, 2.8 million for plasma, and 124 thousand for rear-projection.
In an effort to compete with smaller LCD panels in the market, Vizio released the VP322, a 32" plasma television, in May 2008. This display uses a 32-inch panel made by LG and has a contrast ratio of 30,000:
Plasma displays were first used in PLATO computer terminals. This PLATO V model illustrates the display's monochromatic orange glow as seen in 1981. The monochrome plasma video display was co-invented in 1964 at the University of Illinois at Urbana-Champaign by Donald Bitzer, H. Gene Slottow, and graduate student Robert Willson for the PLATO Computer System. The original neon orange monochrome Digivue display panels built by glass producer Owens-Illinois were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images. A long period of sales decline occurred in the late 1970s because semiconductor memory made CRT displays cheaper than the US$2500 512 x 512 PLATO plasma displays. Nonetheless, the plasma displays' relatively large screen size and 1 inch thickness made them suitable for high-profile placement in lobbies and stock exchanges.
Electrical engineering student Larry F. Weber became interested in plasma displays while studying at the University of Illinois at Urbana-Champaign in the 1960s, and pursued postgraduate work in the field under Bitzer and Slottow. His research eventually earned him 15 patents relating to plasma displays. One of his early contributions was development of the power-saving "energy recovery sustain circuit", now included in every color plasma display.
Burroughs Corporation, a maker of adding machines and computers, developed the Panaplex display in the early 1970s. The Panaplex display, generically referred to as a gas-discharge or gas-plasma display, uses the same technology as later plasma video displays, but began life as seven-segment display for use in adding machines. They became popular for their bright orange luminous look and found nearly ubiquitous use in cash registers, calculators, pinball machines, aircraft avionics such as radios, navigational instruments, and stormscopes; test equipment such as frequency counters and multimeters; and generally anything that previously used nixie tube or numitron displays with a high digit-count throughout the late 1970s and into the 1990s. These displays remained popular until LEDs gained popularity because of their low-current draw and module-flexibility, but are still found in some applications where their high-brightness is desired, such as pinball machines and avionics. Pinball displays started with six- and seven-digit seven-segment displays and later evolved into 16-digit alphanumeric displays, and later into 128x32 dot-matrix displays in 1990, which are still used today.
1983
In 1983, IBM introduced a 19-inch (48 cm) orange-on-black monochrome display (model 3290 'information panel') which was able to show up to four simultaneous IBM 3270 terminal sessions. Due to heavy competition from monochrome LCD's, in 1987 IBM planned to shut down its factory in upstate New York, the largest plasma plant in the world, in favor of manufacturing mainframe computers.[38] Consequently, Larry Weber co-founded a startup company Plasmaco with Stephen Globus, as well as James Kehoe, who was the IBM plant manager, and bought the plant from IBM. Weber stayed in Urbana as CTO until 1990, then moved to upstate New York to work at Plasmaco.
1992
In 1992, Fujitsu introduced the world's first 21-inch (53 cm) full-color display. It was a hybrid, the plasma display created at the University of Illinois at Urbana-Champaign and NHK STRL.
1994
In 1994, Weber demonstrated color plasma technology at an industry convention in San Jose. Panasonic Corporation began a joint development project with Plasmaco, which led in 1996 to the purchase of Plasmaco, its color AC technology, and its American factory.
1997
In 1997, Fujitsu introduced the first 42-inch (107 cm) plasma display; it had 852x480 resolution and was progressively scanned. Also in 1997, Philips introduced a 42-inch (107 cm) display, with 852x480 resolution. It was the only plasma to be displayed to the retail public in 4Sears locations in the US. The price was US$14,999 and included in-home installation. Later in 1997, Pioneer started selling their first plasma television to the public.
2010 - Present
In late 2006, analysts noted that LCDs overtook plasmas, particularly in the 40-inch (1.0 m) and above segment where plasma had previously gained market share. Another industry trend is the consolidation of manufacturers of plasma displays, with around fifty brands available but only five manufacturers. In the first quarter of 2008 a comparison of worldwide TV sales breaks down to 22.1 million for direct-view CRT, 21.1 million for LCD, 2.8 million for Plasma, and 0.1 million for rear-projection.
Until the early 2000s, plasma displays were the most popular choice for HDTV flat panel display as they had many benefits over LCDs. As well as superior brightness, faster response time, greater color spectrum, and wider viewing angle; they were also much bigger than LCDs, and it was believed that LCD technology was suited only to smaller sized televisions. However, improvements in VLSI fabrication technology have since narrowed the technological gap. The increased size, lower weight, falling prices, and often lower electrical power consumption of LCDs now make them competitive with plasma television sets.
Screen sizes have increased since the introduction of plasma displays. The largest plasma video display in the world at the 2008 Consumer Electronics Show in Las Vegas, Nevada, U.S., North America was a 150-inch (381 cm) unit manufactured by Matsushita Electrical Industries (Panasonic) standing 6 ft (180 cm) tall by 11 ft (330 cm) wide. At the 2010 Consumer Electronics Show in Las Vegas, Nevada, U.S.,North America Panasonic introduced their 152" 2160p 3D plasma.
The plasma video display was co-invented in 1964 at the University of Illinois at Urbana-Champaign by Donald Bitzer, H. Gene Slottow, and graduate student Robert Willson for the PLATO Computer System. The original monochrome (orange, green, yellow) video display panels were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images. This was followed by a long period of sales decline in the late 1970s, as semiconductor memory made CRT displays cheaper than plasma displays. Nonetheless, the relatively large screen size and thin body of plasma displays made them suitable for high-profile placement in lobbies and stock exchanges.
In 1983, IBM introduced a 19-inch (48-cm) orange-on-black monochrome display (model 3290 'information panel'), which was able to show four simultaneous IBM 3270 virtual machine (VM) terminal sessions. That factory was transferred in 1987 to startup company Plasmaco,[1] which was founded by Dr. Larry F. Weber (one of Dr. Bitzer's students) with Stephen Globus and James Kehoe (who was the IBM plant manager).
In 1992, Fujitsu introduced the world's first 21-inch (53-cm) full-color display. It was a hybrid, based on the plasma display created at the University of Illinois at Urbana-Champaign and the Science & Technical Research Laboratories (STRL) of Japan Broadcasting Corporation (NHK), achieving superior brightness.
In 1996, Matsushita Electrical Industries (Panasonic) purchased Plasmaco, its color AC technology, and its American factory. In 1997, Fujitsu introduced the first 42-inch (107-cm) plasma display. It had a resolution of 852x480 and was progressively scanned.[2] Also in 1997, Pioneer started selling the first plasma television to the public. Many current plasma televisions, thinner and of larger area than their predecessors, are in use. Their thin size allows them to compete with large projection screens.
Since then, plasma displays have become thinner and larger in screen size. The largest plasma video display in the world at the 2008 Consumer Electronics Show in Las Vegas, Nevada, USA, was a 150-inch (381 cm) unit manufactured by Matsushita Electrical Industries (Panasonic) standing six ft (180 cm) tall by 11 ft (330 cm) wide and expected to initially retail at US$150,000.[3][4]
Until quite recently, the superior brightness, faster response time, greater color spectrum, and wider viewing angle of color plasma video displays, when compared with LCD (liquid crystal display) televisions, made them one of the most popular forms of display for HDTV (high-definition television) flat panel displays. For a long time, it was widely believed that LCD technology was suited only for smaller sized televisions and could not compete with plasma technology at larger sizes, particularly 40 inches (100 cm) and above. Since then, improvements in LCD technology have narrowed the technological gap. The lower weight, falling prices, higher available resolution (important for HDTV), and often lower electrical power consumption of LCDs make them competitive with plasma television sets. In late 2006, analysts noted that LCDs were overtaking plasmas, particularly in the important 40-inch (1.0 m) and above segment, where plasmas had previously enjoyed strong dominance.
The industry has also been trending toward the consolidation of manufacturers of plasma displays, with around fifty brands available but only five manufacturers. In the first quarter of 2008, a comparison of worldwide TV sales broke down to 22.1 million for CRT, 21.1 million for LCD, 2.8 million for plasma, and 124 thousand for rear-projection.
In an effort to compete with smaller LCD panels in the market, Vizio released the VP322, a 32" plasma television, in May 2008. This display uses a 32-inch panel made by LG and has a contrast ratio of 30,000:
How does PDP works?
How does PDP works?
3.1 What is plasma?
Figure 3.1 Plasma Generation
The central element in a fluorescent light is a plasma, a gas made up of free-flowing ions (electrically charged atoms) and electrons (negatively charged particles). Under normal conditions, a gas is mainly made up of uncharged particles. That is, the individual gas atoms include equal numbers of protons (positively charged particles in the atom's nucleus) and electrons. The negatively charged electrons perfectly balance the positively charged protons, so the atom has a net charge of zero.
If you introduce many free electrons into the gas by establishing an electrical voltage across it, the situation changes very quickly. The free electrons collide with the atoms, knocking loose other electrons. With a missing electron, an atom loses its balance. It has a net positive charge, making it an ion. In a plasma with an electrical current running through it, negatively charged particles are rushing toward the positively charged area of the plasma, and positively charged particles are rushing toward the negatively charged area.
In this mad rush, particles are constantly bumping into each other. These collisions excite the gas atoms in the plasma, causing them to release photons of energy. (For details on this process, see How Fluorescent Lamps Work.) Xenon and neon atoms, the atoms used in plasma screens, release light photons when they are excited. Mostly, these atoms release ultraviolet light photons, which are invisible to the human eye. But ultraviolet photons can be used to excite visible light photons, as we'll see in the next section.
The xenon, neon, and helium gas in a plasma television is contained in hundreds of thousands of tiny cells positioned between two plates of glass. Long electrodes are also put together between the glass plates, in front of and behind the cells. The address electrodes sit behind the cells, along the rear glass plate. The transparent display electrodes, which are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer, are mounted in front of the cell, along the front glass plate. Control circuitry charges the electrodes that cross paths at a cell, creating a voltage difference between front and back and causing the gas to ionize and form plasma. As the gas ions rush to the electrodes and collide, photons are emitted.
In a monochrome plasma panel, the ionizing state can be maintained by applying a low-level voltage between all the horizontal and vertical electrodes–even after the ionizing voltage is removed. To erase a cell all voltage is removed from a pair of electrodes. This type of panel has inherent memory and does not use phosphors. A small amount of nitrogen is added to the neon to increase hysteresis. In color panels, the back of each cell is coated with a phosphor. The ultraviolet photons emitted by the plasma excite these phosphors to give off colored light. The operation of each cell is thus comparable to that of a fluorescent lamp.
Every pixel is made up of three separate subpixel cells, each with different colored phosphors. One subpixel has a red light phosphor, one subpixel has a green light phosphor and one subpixel has a blue light phosphor. These colors blend together to create the overall color of the pixel, the same as a triad of a shadow mask CRT or color LCD. Plasma panels use pulse-width modulation to control brightness: by varying the pulses of current flowing through the different cells thousands of times per second, the control system can increase or decrease the intensity of each subpixel color to create billions of different combinations of red, green and blue. In this way, the control system can produce most of the visible colors. Plasma displays use the same phosphors as CRTs, which accounts for the extremely accurate color reproduction when viewing television or computer video images (which use an RGB color system designed for CRT display technology).
With phosphor-based electronic displays (including cathode ray and plasma displays), the prolonged display of a menu bar or other static (fixed in place and unchanging) graphical elements over time can create a permanent ghost-like image of these objects since phosphor compounds which emit the light lose their luminosity with use. As a result, when certain areas of the display are used more frequently than others, over time the lower luminosity areas become visible to the naked eye and the result is called burn-in. While a ghost image is the most noticeable effect, a more common result is that the image quality will continuously and gradually decline as luminosity variations develop over time, resulting in a "muddy" looking picture image. Most plasma display producers state a 100,000 hours time before brightness halves, theoretically allowing for over ten years of normal viewing before the display dims significantly.
Plasma displays also exhibit another image retention issue which is sometimes confused with screen burn-in damage. In this mode, when a group of pixels are run at high brightness (when displaying white, for example) for an extended period of time, a charge build-up in the pixel structure occurs and a ghost image can be seen. However, unlike burn-in, this charge build-up is transient and self corrects after the image condition that caused the effect has been removed and a long enough period of time has passed (with the display either off or on).
3.2 Inside a Plasma Display
The xenon and neon gas in a plasma television is contained in hundreds of thousands of tiny cells positioned between two plates of glass. Long electrodes are also sandwiched between the glass plates, on both sides of the cells. The address electrodes sit behind the cells, along the rear glass plate. The transparent display electrodes, which are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer, are mounted above the cell, along the front glass plate.
Both sets of electrodes extend across the entire screen. The display electrodes are arranged in horizontal rows along the screen and the address electrodes are arranged in vertical columns. As you can see in the diagram below, the vertical and horizontal electrodes form a basic grid.
Figure 3.2 inside Plasma
To ionize the gas in a particular cell, the plasma display's computer charges the electrodes that intersect at that cell. It does this thousands of times in a small fraction of a second, charging each cell in turn.
Figure 3.3 Imaging Process
When the intersecting electrodes are charged (with a voltage difference between them), an electric current flows through the gas in the cell. As we saw in the last section, the current creates a rapid flow of charged particles, which stimulates the gas atoms to release ultraviolet photons.
The released ultraviolet photons interact with phosphor material coated on the inside wall of the cell. Phosphors are substances that give off light when they are exposed to other light. When an ultraviolet photon hits a phosphor atom in the cell, one of the phosphor's electrons jumps to a higher energy level and the atom heats up. When the electron falls back to its normal level, it releases energy in the form of a visible light photon.
The phosphors in a plasma display give off colored light when they are excited. Every pixel is made up of three separate sub pixel cells, each with different colored phosphors. One sub pixel has a red light phosphor, one sub pixel has a green light phosphor and one sub pixel has a blue light phosphor. These colors blend together to create the overall color of the pixel.
By varying the pulses of current flowing through the different cells, the control system can increase or decrease the intensity of each sub pixel color to create hundreds of different combinations of red, green and blue. In this way, the control system can produce colors across the entire spectrum.
The main advantage of plasma display technology is that you can produce a very wide screen using extremely thin materials. And because each pixel is lit individually, the image is very bright and looks good from almost every angle. The image quality isn't quite up to the standards of the best cathode ray tube sets, but it certainly meets most people's expectations.
The biggest drawback of this technology has been the price. However, falling prices and advances in technology mean that the plasma display may soon edge out the old CRT sets.
To learn more about plasma displays, as well as other television technologies, check out the links on the next page.
3.1 What is plasma?
Figure 3.1 Plasma Generation
The central element in a fluorescent light is a plasma, a gas made up of free-flowing ions (electrically charged atoms) and electrons (negatively charged particles). Under normal conditions, a gas is mainly made up of uncharged particles. That is, the individual gas atoms include equal numbers of protons (positively charged particles in the atom's nucleus) and electrons. The negatively charged electrons perfectly balance the positively charged protons, so the atom has a net charge of zero.
If you introduce many free electrons into the gas by establishing an electrical voltage across it, the situation changes very quickly. The free electrons collide with the atoms, knocking loose other electrons. With a missing electron, an atom loses its balance. It has a net positive charge, making it an ion. In a plasma with an electrical current running through it, negatively charged particles are rushing toward the positively charged area of the plasma, and positively charged particles are rushing toward the negatively charged area.
In this mad rush, particles are constantly bumping into each other. These collisions excite the gas atoms in the plasma, causing them to release photons of energy. (For details on this process, see How Fluorescent Lamps Work.) Xenon and neon atoms, the atoms used in plasma screens, release light photons when they are excited. Mostly, these atoms release ultraviolet light photons, which are invisible to the human eye. But ultraviolet photons can be used to excite visible light photons, as we'll see in the next section.
The xenon, neon, and helium gas in a plasma television is contained in hundreds of thousands of tiny cells positioned between two plates of glass. Long electrodes are also put together between the glass plates, in front of and behind the cells. The address electrodes sit behind the cells, along the rear glass plate. The transparent display electrodes, which are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer, are mounted in front of the cell, along the front glass plate. Control circuitry charges the electrodes that cross paths at a cell, creating a voltage difference between front and back and causing the gas to ionize and form plasma. As the gas ions rush to the electrodes and collide, photons are emitted.
In a monochrome plasma panel, the ionizing state can be maintained by applying a low-level voltage between all the horizontal and vertical electrodes–even after the ionizing voltage is removed. To erase a cell all voltage is removed from a pair of electrodes. This type of panel has inherent memory and does not use phosphors. A small amount of nitrogen is added to the neon to increase hysteresis. In color panels, the back of each cell is coated with a phosphor. The ultraviolet photons emitted by the plasma excite these phosphors to give off colored light. The operation of each cell is thus comparable to that of a fluorescent lamp.
Every pixel is made up of three separate subpixel cells, each with different colored phosphors. One subpixel has a red light phosphor, one subpixel has a green light phosphor and one subpixel has a blue light phosphor. These colors blend together to create the overall color of the pixel, the same as a triad of a shadow mask CRT or color LCD. Plasma panels use pulse-width modulation to control brightness: by varying the pulses of current flowing through the different cells thousands of times per second, the control system can increase or decrease the intensity of each subpixel color to create billions of different combinations of red, green and blue. In this way, the control system can produce most of the visible colors. Plasma displays use the same phosphors as CRTs, which accounts for the extremely accurate color reproduction when viewing television or computer video images (which use an RGB color system designed for CRT display technology).
With phosphor-based electronic displays (including cathode ray and plasma displays), the prolonged display of a menu bar or other static (fixed in place and unchanging) graphical elements over time can create a permanent ghost-like image of these objects since phosphor compounds which emit the light lose their luminosity with use. As a result, when certain areas of the display are used more frequently than others, over time the lower luminosity areas become visible to the naked eye and the result is called burn-in. While a ghost image is the most noticeable effect, a more common result is that the image quality will continuously and gradually decline as luminosity variations develop over time, resulting in a "muddy" looking picture image. Most plasma display producers state a 100,000 hours time before brightness halves, theoretically allowing for over ten years of normal viewing before the display dims significantly.
Plasma displays also exhibit another image retention issue which is sometimes confused with screen burn-in damage. In this mode, when a group of pixels are run at high brightness (when displaying white, for example) for an extended period of time, a charge build-up in the pixel structure occurs and a ghost image can be seen. However, unlike burn-in, this charge build-up is transient and self corrects after the image condition that caused the effect has been removed and a long enough period of time has passed (with the display either off or on).
3.2 Inside a Plasma Display
The xenon and neon gas in a plasma television is contained in hundreds of thousands of tiny cells positioned between two plates of glass. Long electrodes are also sandwiched between the glass plates, on both sides of the cells. The address electrodes sit behind the cells, along the rear glass plate. The transparent display electrodes, which are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer, are mounted above the cell, along the front glass plate.
Both sets of electrodes extend across the entire screen. The display electrodes are arranged in horizontal rows along the screen and the address electrodes are arranged in vertical columns. As you can see in the diagram below, the vertical and horizontal electrodes form a basic grid.
Figure 3.2 inside Plasma
To ionize the gas in a particular cell, the plasma display's computer charges the electrodes that intersect at that cell. It does this thousands of times in a small fraction of a second, charging each cell in turn.
Figure 3.3 Imaging Process
When the intersecting electrodes are charged (with a voltage difference between them), an electric current flows through the gas in the cell. As we saw in the last section, the current creates a rapid flow of charged particles, which stimulates the gas atoms to release ultraviolet photons.
The released ultraviolet photons interact with phosphor material coated on the inside wall of the cell. Phosphors are substances that give off light when they are exposed to other light. When an ultraviolet photon hits a phosphor atom in the cell, one of the phosphor's electrons jumps to a higher energy level and the atom heats up. When the electron falls back to its normal level, it releases energy in the form of a visible light photon.
The phosphors in a plasma display give off colored light when they are excited. Every pixel is made up of three separate sub pixel cells, each with different colored phosphors. One sub pixel has a red light phosphor, one sub pixel has a green light phosphor and one sub pixel has a blue light phosphor. These colors blend together to create the overall color of the pixel.
By varying the pulses of current flowing through the different cells, the control system can increase or decrease the intensity of each sub pixel color to create hundreds of different combinations of red, green and blue. In this way, the control system can produce colors across the entire spectrum.
The main advantage of plasma display technology is that you can produce a very wide screen using extremely thin materials. And because each pixel is lit individually, the image is very bright and looks good from almost every angle. The image quality isn't quite up to the standards of the best cathode ray tube sets, but it certainly meets most people's expectations.
The biggest drawback of this technology has been the price. However, falling prices and advances in technology mean that the plasma display may soon edge out the old CRT sets.
To learn more about plasma displays, as well as other television technologies, check out the links on the next page.
PDP Technology
PDP Technology
• Plasma monitors and TVs are emissive in operation
• Image brightness directly related to intensity at which individual
pixels are driven
• Current PDP benchmarks include sizes to 102” (prototypes) and brightness exceeding 100 nits (FW)
• Power draw 15-20% more than LCD for given size
• Weight 20-25% more than LCD for given size
• Plasma monitors and TVs are emissive in operation
• Image brightness directly related to intensity at which individual
pixels are driven
• Current PDP benchmarks include sizes to 102” (prototypes) and brightness exceeding 100 nits (FW)
• Power draw 15-20% more than LCD for given size
• Weight 20-25% more than LCD for given size
Plasma
1.1 What is Plasma Display Panels?
A plasma display panel (PDP) is a type of flat panel display common to large TV displays (80 cm or larger). Many tiny cells between just two panels of glass hold a mixture of noble gases. The gas in the cells is electrically turned into plasma which emits ultraviolet light which then excites phosphors to emit visible light. Plasma displays should not be confused with LCDs, another lightweight flat screen display using different technology. We see this more and more on store signs and in ads promoting large-screen, flat-panel plasma TVs. The flat plasma display is a major competitor among several flat panel display technologies – all vying for the potentially enormous High Definition TV market.
For many people, the word “Plasma” has come to mean only display screens. As impressive as those displays are, the word refers much more generally to a special state of matter that resides not only inside those display panels, producing their light and images, but also in many other devices we use every day. In some cases plasma is part of a product’s manufacturing process. In addition, plasmas fill much of our surrounding universe. Plasma is a gas containing a large number of electrically charged particles, both negatively-charged electrons and positively-charged atoms, called ions. In most plasma, including those in the plasma display panel, there also remains a large number of uncharged particles (called the “background gas”). The plasma in a display panel is much like the plasma in another familiar device, the fluorescent lamp. A plasma display panel (PDP) is essentially a collection of very small fluorescent-type lamps, each a few tenths of a millimeter in size. If we look closely, it is easy to distinguish the individual PDP cells – the tiny color elements of red, green and blue light that together form what is called a pixel. As in a fluorescent lamp, the light we see does not come from the plasma directly, but rather from the phosphor coatings on the inside walls of the cells when they are exposed to ultraviolet (UV) radiation emitted by the plasma. Because each cell emits its own light, a plasma display panel is called an “emissive display.” This contrasts with the familiar liquid crystal display (LCD), a type of flat display in which the light comes from a lamp (actually a plasma lamp!) behind the liquid crystal, which has arrays of small switches controlling where light is allowed to pass through.
All plasmas require a source of energy. As in fluorescent lamps, the plasma in a PDP is produced by applying a voltage across a gap that contains gas. The plasmas used in PDPs are considered "cold" plasmas in the sense that the background gas stays relatively cold while the electrons (and ions) in the plasma are heated by the applied voltage. When the hot electrons collide with the background gas atoms and transfer energy to them, many of those atoms respond by emitting UV radiation. The operating conditions of the display (gas composition, pressure, voltage, geometry, etc.) represent a compromise, taking into account performance requirements such as low voltage operation, long life, high brightness and high contrast.
The plasma display itself is a simple device consisting of two parallel glass plates separated by a precise spacing of some tenths of a millimeter and sealed around the edges. The space between the plates is filled with a mixture of rare gases at a pressure somewhat less than one atmosphere. Parallel stripes of transparent conducting material with a width of about a tenth of a millimeter are deposited on each plate, with the stripes on one plate perpendicular to those on the other.
These stripes are the "electrodes" to which voltages are applied. The intersections of the rows of electrodes on one side and the columns of electrodes on the opposite glass plate define the individual color elements – or cells – of a PDP.
High quality color images it is important to keep the UV radiation from passing between cells. To isolate the individual cells barriers are created on the inside surface of one of the plates before sealing. Troughs, honeycomb-like structures and other shapes have been used. The red, green and blue phosphors are deposited inside these structures. An important feature of PDPs is that the plasma in each individual cell can be turned on and off rapidly enough to produce a high quality moving picture. (To help turn the individual cells on and off, there are actually two electrodes on one side and a third electrode on the opposite side of each cell.) Switching the cells on and off cheaply and efficiently is now possible because of advances over the past 20 years in the miniaturization and efficiency of electronics. A commercial panel consists of several million cells which have to be switched at a rate that will create 60 TV picture frames per second. A computer translates an image into a sequence of on and off voltage pulses which are applied to the electrode arrays line by line and row by row to select individual cells. Such control is possible because the plasma is fast and can respond to the voltage pulses in a millionth of a second. The complexity increases significantly when we consider that each small picture element, or pixel, consists of three color cells, and each color cell can display 256 intensity levels.
Thus each pixel can display over 16.7 million (or, more exactly, 256x256x256) colors. Variation in light intensity from a particular cell is not accomplished by changing the voltage or the current through the cell. Rather, it is achieved by changing the length of time that the cell is ON during one TV frame. Since the eye response is slower than the TV picture frequency, it perceives different colors depending on how long each cell is ON. Each company has made its own contribution to the switching systems to improve efficiency, speed and performance. Many years of research and development as well as major advances in electronics and manufacturing techniques have led to the plasma display panels we see on the market today. The plasma display panel itself was invented in 1964 by researchers at the University of Illinois, with the first PDPs being single-color (or “monochrome”) displays. Research on multi-color PDPs was going strong in the 1980's, and the first commercially available color displays appeared in the late 1990’s. It is now possible to manufacture PDPs with diagonals as large as 80 inches and with a thickness of only 3 to 4 inches. Considerable progress has also been made recently to reduce the power consumption and increase the efficiency and life-time of PDPs. Large screens, excellent image quality and brightness, and greater than 160° viewing angle characterize today's plasma panels, which are perfectly flat and perform well even in bright environments. Long-term commercial success of the PDP now lies in the manufacturers' ability to produce low cost displays. Significant reductions in costs have been realized over the last few years, and new PDP designs and processes are being introduced all the time, continuing to reduce production costs. The PDP is sure to be one of the predominant large-format displays of the future.
Fig1.1 Plasma Display Panel
Plasma displays are bright (1,000 lux or higher for the module), have a wide color gamut, and can be produced in fairly large sizes—up to 3.8 m (150 inches) diagonally. They have a very low-luminance "dark-room" black level compared to the lighter grey of the unilluminated parts of an LCD screen. The display panel itself is only about 6 cm (2.5 inches) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (4 inches). Plasma displays use as much power per square meter as a CRT or an AMLCD television. Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones - this is also true of CRTs. Typical power consumption is 400 watts for a 50-inch (127 cm) screen. 20 to 310 watts for a 50-inch (127 cm) display when set to cinema mode. Most screens are set to 'shop' mode by default, which draws at least twice the power (around 500-700 watts) of a 'home' setting of less extreme brightness. Panasonic has greatly reduced power consumption by using Neo-PDP screens in their 2009 series of Viera plasma HDTVs. Panasonic claims that PDPs will consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value.
Plasma display screens are made from glass, which reflects more light than the material used to make an LCD screen. This causes glare from reflected objects in the viewing area. Companies such as Panasonic coat their newer plasma screens with an anti-glare filter material. Currently, plasma panels cannot be economically manufactured in screen sizes smaller than 32 inches. Although a few companies have been able to make plasma EDTVs this small, even fewer have made 32in plasma HDTVs. With the trend toward larger and larger displays, the 32in screen size is rapidly disappearing. Though considered bulky and thick compared to their LCD counterparts, some sets such as Panasonic's Z1 and Samsung's B860 series are as slim as one inch thick making them comparable to LCDs in this respect.
A plasma display panel (PDP) is a type of flat panel display common to large TV displays (80 cm or larger). Many tiny cells between just two panels of glass hold a mixture of noble gases. The gas in the cells is electrically turned into plasma which emits ultraviolet light which then excites phosphors to emit visible light. Plasma displays should not be confused with LCDs, another lightweight flat screen display using different technology. We see this more and more on store signs and in ads promoting large-screen, flat-panel plasma TVs. The flat plasma display is a major competitor among several flat panel display technologies – all vying for the potentially enormous High Definition TV market.
For many people, the word “Plasma” has come to mean only display screens. As impressive as those displays are, the word refers much more generally to a special state of matter that resides not only inside those display panels, producing their light and images, but also in many other devices we use every day. In some cases plasma is part of a product’s manufacturing process. In addition, plasmas fill much of our surrounding universe. Plasma is a gas containing a large number of electrically charged particles, both negatively-charged electrons and positively-charged atoms, called ions. In most plasma, including those in the plasma display panel, there also remains a large number of uncharged particles (called the “background gas”). The plasma in a display panel is much like the plasma in another familiar device, the fluorescent lamp. A plasma display panel (PDP) is essentially a collection of very small fluorescent-type lamps, each a few tenths of a millimeter in size. If we look closely, it is easy to distinguish the individual PDP cells – the tiny color elements of red, green and blue light that together form what is called a pixel. As in a fluorescent lamp, the light we see does not come from the plasma directly, but rather from the phosphor coatings on the inside walls of the cells when they are exposed to ultraviolet (UV) radiation emitted by the plasma. Because each cell emits its own light, a plasma display panel is called an “emissive display.” This contrasts with the familiar liquid crystal display (LCD), a type of flat display in which the light comes from a lamp (actually a plasma lamp!) behind the liquid crystal, which has arrays of small switches controlling where light is allowed to pass through.
All plasmas require a source of energy. As in fluorescent lamps, the plasma in a PDP is produced by applying a voltage across a gap that contains gas. The plasmas used in PDPs are considered "cold" plasmas in the sense that the background gas stays relatively cold while the electrons (and ions) in the plasma are heated by the applied voltage. When the hot electrons collide with the background gas atoms and transfer energy to them, many of those atoms respond by emitting UV radiation. The operating conditions of the display (gas composition, pressure, voltage, geometry, etc.) represent a compromise, taking into account performance requirements such as low voltage operation, long life, high brightness and high contrast.
The plasma display itself is a simple device consisting of two parallel glass plates separated by a precise spacing of some tenths of a millimeter and sealed around the edges. The space between the plates is filled with a mixture of rare gases at a pressure somewhat less than one atmosphere. Parallel stripes of transparent conducting material with a width of about a tenth of a millimeter are deposited on each plate, with the stripes on one plate perpendicular to those on the other.
These stripes are the "electrodes" to which voltages are applied. The intersections of the rows of electrodes on one side and the columns of electrodes on the opposite glass plate define the individual color elements – or cells – of a PDP.
High quality color images it is important to keep the UV radiation from passing between cells. To isolate the individual cells barriers are created on the inside surface of one of the plates before sealing. Troughs, honeycomb-like structures and other shapes have been used. The red, green and blue phosphors are deposited inside these structures. An important feature of PDPs is that the plasma in each individual cell can be turned on and off rapidly enough to produce a high quality moving picture. (To help turn the individual cells on and off, there are actually two electrodes on one side and a third electrode on the opposite side of each cell.) Switching the cells on and off cheaply and efficiently is now possible because of advances over the past 20 years in the miniaturization and efficiency of electronics. A commercial panel consists of several million cells which have to be switched at a rate that will create 60 TV picture frames per second. A computer translates an image into a sequence of on and off voltage pulses which are applied to the electrode arrays line by line and row by row to select individual cells. Such control is possible because the plasma is fast and can respond to the voltage pulses in a millionth of a second. The complexity increases significantly when we consider that each small picture element, or pixel, consists of three color cells, and each color cell can display 256 intensity levels.
Thus each pixel can display over 16.7 million (or, more exactly, 256x256x256) colors. Variation in light intensity from a particular cell is not accomplished by changing the voltage or the current through the cell. Rather, it is achieved by changing the length of time that the cell is ON during one TV frame. Since the eye response is slower than the TV picture frequency, it perceives different colors depending on how long each cell is ON. Each company has made its own contribution to the switching systems to improve efficiency, speed and performance. Many years of research and development as well as major advances in electronics and manufacturing techniques have led to the plasma display panels we see on the market today. The plasma display panel itself was invented in 1964 by researchers at the University of Illinois, with the first PDPs being single-color (or “monochrome”) displays. Research on multi-color PDPs was going strong in the 1980's, and the first commercially available color displays appeared in the late 1990’s. It is now possible to manufacture PDPs with diagonals as large as 80 inches and with a thickness of only 3 to 4 inches. Considerable progress has also been made recently to reduce the power consumption and increase the efficiency and life-time of PDPs. Large screens, excellent image quality and brightness, and greater than 160° viewing angle characterize today's plasma panels, which are perfectly flat and perform well even in bright environments. Long-term commercial success of the PDP now lies in the manufacturers' ability to produce low cost displays. Significant reductions in costs have been realized over the last few years, and new PDP designs and processes are being introduced all the time, continuing to reduce production costs. The PDP is sure to be one of the predominant large-format displays of the future.
Fig1.1 Plasma Display Panel
Plasma displays are bright (1,000 lux or higher for the module), have a wide color gamut, and can be produced in fairly large sizes—up to 3.8 m (150 inches) diagonally. They have a very low-luminance "dark-room" black level compared to the lighter grey of the unilluminated parts of an LCD screen. The display panel itself is only about 6 cm (2.5 inches) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (4 inches). Plasma displays use as much power per square meter as a CRT or an AMLCD television. Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones - this is also true of CRTs. Typical power consumption is 400 watts for a 50-inch (127 cm) screen. 20 to 310 watts for a 50-inch (127 cm) display when set to cinema mode. Most screens are set to 'shop' mode by default, which draws at least twice the power (around 500-700 watts) of a 'home' setting of less extreme brightness. Panasonic has greatly reduced power consumption by using Neo-PDP screens in their 2009 series of Viera plasma HDTVs. Panasonic claims that PDPs will consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value.
Plasma display screens are made from glass, which reflects more light than the material used to make an LCD screen. This causes glare from reflected objects in the viewing area. Companies such as Panasonic coat their newer plasma screens with an anti-glare filter material. Currently, plasma panels cannot be economically manufactured in screen sizes smaller than 32 inches. Although a few companies have been able to make plasma EDTVs this small, even fewer have made 32in plasma HDTVs. With the trend toward larger and larger displays, the 32in screen size is rapidly disappearing. Though considered bulky and thick compared to their LCD counterparts, some sets such as Panasonic's Z1 and Samsung's B860 series are as slim as one inch thick making them comparable to LCDs in this respect.
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