Telecommunications in India

TelephoneCommunications in Indiacommunications
As the unbranded Chinese cell phones which do not have International Mobile Equipment Identity (IMEI) numbers pose a serious security risk to the country, Mobile network operators therefore suspended the usage of around 30 million mobile phones (about 8% of all mobiles in the country) by 30 April 2009. Phones without valid IMEI cannot be connected to cellular operators. India has opted for the use of both the GSM (global system for mobile communications) and CDMA (code-division multiple access) technologies in the mobile sector. In addition to landline and mobile phones, some of the companies also provide the WLL service. The mobile tariffs in India have also become the lowest in the world.

History of telecommunication

History of telecommunicationsenormously increased speed of telecommunicationsprogress
Black in 1980, has since been the industry standard for digital telephony. By the 1990s, telecommunication networks such as the public switched telephone network (PSTN) had been largely digitized with very-large-scale integration (VLSI) CMOS PCM codec-filters, widely used in electronic switching systems for telephone exchanges and data transmission applications. Practical digital media distribution and streaming was made possible by advances in data compression, due to the impractically high memory, storage and bandwidth requirements of uncompressed media.


On April 28, 2008 Jajah provideds its proprietary telephony infrastructure, payment processing, and customer care to Yahoo! Messenger users using the platform for receiving calls from the PSTN network, or for making calls to land lines and mobile phones. Telefónica bought Jajah for a reported $207 million on December 23, 2009. On April 14, 2011, Jajah announced a partnership with Globe Telecom to allow Filipinos living outside Philippines to call home at inexpensive rate. It announced November 30, 2012 that effective January 30, 2013, Yahoo! Messenger will no longer offer Yahoo! Voice Phone In and Phone Out capabilities, the co-branded landline and mobile phone service from Jajah.

Telecommunications relay service

captioned telephone7-1-1IP Relay
A telecommunications relay service, also known as TRS, relay service, or IP-relay, or Web-based relay service, is an operator service that allows people who are deaf, hard of hearing, deafblind, or have a speech disorder to place calls to standard telephone users via a keyboard or assistive device. Originally, relay services were designed to be connected through a TDD, teletypewriter (TTY) or other assistive telephone device. Services gradually have expanded to include almost any real-time text capable technology such as a personal computer, laptop, mobile phone, PDA, and many other devices. The first TTY was invented by deaf scientist Robert Weitbrecht in 1964.

Cellular network

cellularmobile networkcellular networks
., mobile phones, tablets and laptops equipped with mobile broadband modems, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission. Cellular networks offer a number of desirable features: Major telecommunications providers have deployed voice and data cellular networks over most of the inhabited land area of Earth. This allows mobile phones and mobile computing devices to be connected to the public switched telephone network and public Internet.

Kayvan Novak

In 2005, he and Ed Tracy created Fonejacker, a prank call show as part of Channel 4's Comedy Lab strand. After the pilot, he was given a Christmas special and a six-part series, which began airing on 5 July 2007 on E4 and 7 September 2007 on Channel 4. In November 2009, he appeared on the Channel 4 show The Increasingly Poor Decisions of Todd Margaret, playing a bomb disposal officer. In April 2010, Novak began appearing in a spin-off of Fonejacker called Facejacker, in which he adopted various disguises, including several characters heard in Fonejacker.

Digital subscriber line

DSLxDSLDigital Subscriber Line (DSL)
A naked DSL (also known as standalone or dry loop DSL) is a way of providing DSL services without a PSTN (analogue telephony) service. It is useful when the customer does not need the traditional telephony voice service because voice service is received either on top of the DSL services (usually VoIP) or through another network (mobile telephony). It is also commonly called a UNE (for unbundled network element) in the United States; in Australia it is known as a ULL (unconditioned local loop); in Belgium it is known as "raw copper" and in the UK it is known as Single Order GEA (SoGEA).


metal-oxide-semiconductorMOSMOS integrated circuit
, including push-button telephones, digital telephones, speed dial, touch-tone phones, payphones, cordless telephones, cell phones, digital cordless telephones, digital cell phones, camera phones, and videophones. • Telephone networks, including public switched telephone network (PSTN), electronic switching system (ESS), telephone exchange, private branch exchange (PBX), key telephone system (KTS), and telephone loop extenders. • Telephony, including telephone switching, digital telephony, voice mail, digital tapeless answering machines, and pair gain multiplexers. • Television (TV), including TV systems, TV receivers, TV receiver circuits, large-screen television technology, terrestrial broadcast

Local loop

subscriber lineloopsubscriber loop
In telephony, the local loop (also referred to as the local tail, subscriber line, or in the aggregate as the last mile) is the physical link or circuit that connects from the demarcation point of the customer premises to the edge of the common carrier or telecommunications service provider's network. At the edge of the carrier access network in a traditional public telephone network, the local loop terminates in a circuit switch housed in an incumbent local exchange carrier or telephone exchange. Traditionally, the local loop was an electrical circuit in the form of a single pair of conductors from the telephone on the customer's premises to the local telephone exchange.

Telephone line

phone linelinetelephone cable
A telephone line or telephone circuit (or just line or circuit within the industry) is a single-user circuit on a telephone communication system. This is the physical wire or other signaling medium connecting the user's telephone apparatus to the telecommunications network, and usually also implies a single telephone number for billing purposes reserved for that user. Telephone lines are used to deliver landline telephone service and Digital subscriber line (DSL) phone cable service to the premises. Telephone overhead lines are connected to the public switched telephone network.

Backbone network

core networkbackbonenetwork backbone
The theory, design principles, and first instantiation of the backbone network came from the telephone core network, when traffic was purely voice. The core network was the central part of a telecommunications network that provided various services to customers who were connected by the access network. One of the main functions was to route telephone calls across the PSTN. Typically the term referred to the high capacity communication facilities that connect primary nodes. A core network provided paths for the exchange of information between different sub-networks.


wireless communicationwireless communicationswireless internet
The wireless revolution began in the 1990s, with the advent of digital wireless networks leading to a social revolution, and a paradigm shift from wired to wireless technology, including the proliferation of commercial wireless technologies such as cell phones, mobile telephony, pagers, wireless computer networks, cellular networks, the wireless Internet, and laptop and handheld computers with wireless connections.

Radio-frequency engineering

radio electronicsRF circuitRF engineering
It is incorporated into almost everything that transmits or receives a radio wave, which includes, but is not limited to, mobile phones, radios, Wi-Fi, and two-way radios. RF engineering is a highly specialized field that typically includes the following areas of expertise: To produce quality results, the RF engineer needs an in-depth knowledge of mathematics, physics and general electronics theory as well as specialized training in areas such as wave propagation, impedance transformations, filters and microstrip printed circuit board design. Radio electronics is concerned with electronic circuits which receive or transmit radio signals.

Signaling (telecommunications)

signalsignalingout-of-band signaling
In the public switched telephone network (PSTN), in-band signaling is the exchange of call control information within the same physical channel, or within the same frequency band, that the telephone call itself is using. An example is dual-tone multi-frequency signaling (DTMF), which is used on most telephone lines to customer premises. Out-of-band signaling is telecommunication signaling on a dedicated channel separate from that used for the telephone call. Out-of-band signaling has been used since Signaling System No. 6 (SS6) was introduced in the 1970s, and also in Signalling System No. 7 (SS7) in 1980 which became the standard for signaling among exchanges ever since.

Digital signal processing

DSPsignal processingdigital
Specific examples include speech coding and transmission in digital mobile phones, room correction of sound in hi-fi and sound reinforcement applications, weather forecasting, economic forecasting, seismic data processing, analysis and control of industrial processes, medical imaging such as CAT scans and MRI, MP3 compression, computer graphics, image manipulation, audio crossovers and equalization, and audio effects units. DSP algorithms may be run on general-purpose computers and digital signal processors. DSP algorithms are also implemented on purpose-built hardware such as application-specific integrated circuit (ASICs).


CCITTITU Telecommunication Standardization SectorTelecommunication Standardization Sector
The ITRs go back to the earliest days of the ITU when there were two separate treaties, dealing with telegraph and telephone. The ITRs were adopted, as a single treaty, at the World Administrative Telegraphy and Telephone Conference held in Melbourne, 1988 (WATTC-88). The ITRs comprise ten articles which deal, inter alia, with the definition of international telecommunication services, cooperation between countries and national administrations, safety of life and priority of telecommunications and charging and accounting principles.

Telephone exchange names

central office nametelephone exchangetelephone exchange name
This extended the usable numbering plan and only two area code splits became necessary between 1962 and 1981. All-number calling was phased in starting in 1958 and most areas had adopted it fully by the mid-1960s. In some areas it did not become universal until the 1980s. The Bell System published and distributed area code handbooks yearly which compiled the towns available for calling using an area code. Experiencing significant resistance in many areas, the Bell System employed a strategy of gradual changes to ease the transition for customers.


RF CMOScomplementary metal–oxide–semiconductorcomplementary MOS
The baseband processors and radio transceivers in all modern wireless networking devices and mobile phones are mass-produced using RF CMOS devices. RF CMOS circuits are widely used to transmit and receive wireless signals, in a variety of applications, such as satellite technology (such as GPS), bluetooth, Wi-Fi, near-field communication (NFC), mobile networks (such as 3G and 4G), terrestrial broadcast, and automotive radar applications, among other uses. Examples of commercial RF CMOS chips include Intel's DECT cordless phone, and 802.11 (Wi-Fi) chips created by Atheros and other companies. Commercial RF CMOS products are also used for Bluetooth and Wireless LAN (WLAN) networks.

Bruce Almighty

Since God contacts Bruce using an actual phone number rather than a number in the standard fictional 555 telephone exchange, several people and groups sharing this number subsequently received hundreds of phone calls from people wanting to talk to God, including a church in North Carolina (where the minister was named Bruce), a Pastor in Northern Wisconsin and a man in Manchester, England. The producers noted that the number (776-2323) was not in use in the area code (716, which was never specified on screen) in the film's story but did not check anywhere else. The home video and television versions changed it to the fictional 555-0123.

Disruptive innovation

disruptive technologydisruptive technologiesdisruption
In business theory, a disruptive innovation is an innovation that creates a new market and value network and eventually disrupts an existing market and value network, displacing established market-leading firms, products, and alliances. The term was defined and first analyzed by the American scholar Clayton M. Christensen and his collaborators beginning in 1995, and has been called the most influential business idea of the early 21st century.


WiFiwireless internetwireless
The United Kingdom's Health Protection Agency reported in 2007 that exposure to Wi-Fi for a year results in the "same amount of radiation from a 20-minute mobile phone call". A review of studies involving 725 people who claimed electromagnetic hypersensitivity, "...suggests that 'electromagnetic hypersensitivity' is unrelated to the presence of an EMF, although more research into this phenomenon is required."


smartphonessmart phonesmart phones
It could instantly transmit pictures via cell phone telecommunication. By the mid-2000s, higher-end cell phones commonly had integrated digital cameras. In 2003 camera phones outsold stand-alone digital cameras, and in 2006 they outsold film and digital stand-alone cameras. Five billion camera phones were sold in five years, and by 2007 more than half of the installed base of all mobile phones were camera phones. Sales of separate cameras peaked in 2008. Many early smartphones didn't have cameras at all, and earlier models that had them had low performance and insufficient image and video quality that could not compete with budget pocket cameras and fullfill user's needs.

GSM services

servicesmobile data serviceAdvice of Charge
Once a mobile phone has successfully attached to a GSM network as described above, calls may be made from the phone to any other phone on the global Public Switched Telephone Network. The user dials the telephone number, presses the send or talk key, and the mobile phone sends a call setup request message to the mobile phone network via the nearest mobile phone base transceiver station (BTS). The call setup request message is handled next by the Mobile Switching Center, which checks the subscriber's record held in the Visitor Location Register to see if the outgoing call is allowed. If so, the MSC then routes the call in the same way that a telephone exchange does in a fixed network.

John Francis Mitchell

John F. Mitchell
Prior to the development of the cell phone, Mitchell and his team of engineers produced and marketed the first transistorized pager and obtained a patent for the concept of portable cell telephony, including small antennae used to help free mobile phone units from car trunks where they were typically installed. Mitchell, Motorola's chief of portable communication products and Martin Cooper's boss in 1973, played a key role in advancing the development of handheld mobile telephone equipment. Mitchell successfully pushed Motorola to develop wireless communication products that would be small enough to use anywhere and participated in the design of the cellular phone.


swattedfalse report about a stabbingplay it for a 911 operator
Caller ID spoofing, social engineering, TTY, prank calls, and phone phreaking techniques may be variously combined by swatting perpetrators. 911 systems (including computer telephony systems and human operators) have been tricked by calls placed from cities hundreds of miles away from the location of the purported call, or even from other countries. The caller typically places a 911 call using a spoofed phone number (so as to hide the fraudulent caller's real location) with the goal of tricking emergency authorities into responding with a SWAT team to a fabricated emergency.