1.
3G
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3G, short for third generation, is the third generation of wireless mobile telecommunications technology. Later 3G releases, often denoted 3. 5G and 3. 75G, also mobile broadband access of several Mbit/s to smartphones. This ensures it can be applied to voice telephony, mobile Internet access, fixed wireless Internet access, video calls. A new generation of cellular standards has appeared approximately every year since 1G systems were introduced in 1981/1982. Each generation is characterized by new bands, higher data rates. The first 3G networks were introduced in 1998 and fourth generation 4G networks in 2008, several telecommunications companies market wireless mobile Internet services as 3G, indicating that the advertised service is provided over a 3G wireless network. Services advertised as 3G are required to meet IMT-2000 technical standards, including standards for reliability, to meet the IMT-2000 standards, a system is required to provide peak data rates of at least 200 kbit/s. However, many services advertised as 3G provide higher speed than the technical requirements for a 3G service. Recent 3G releases, often denoted 3. 5G and 3. 75G, also mobile broadband access of several Mbit/s to smartphones. The cell phones are typically UMTS and GSM hybrids, several radio interfaces are offered, sharing the same infrastructure, The original and most widespread radio interface is called W-CDMA. The TD-SCDMA radio interface was commercialized in 2009 and is offered in China. The latest UMTS release, HSPA+, can provide data rates up to 56 Mbit/s in the downlink in theory and 22 Mbit/s in the uplink. The CDMA2000 system, first offered in 2002, standardized by 3GPP2, used especially in North America and South Korea, the cell phones are typically CDMA2000 and IS-95 hybrids. The latest release EVDO Rev B offers peak rates of 14.7 Mbit/s downstream, the above systems and radio interfaces are based on spread spectrum radio transmission technology. It is based on the three times as efficient 8PSK modulation scheme as supplement to the original GMSK modulation scheme, EDGE is still used extensively due to its ease of upgrade from existing 2G GSM infrastructure and cell-phones. However, in practice EDGE is seldom marketed as a 3G system, EDGE was also a mode in the IS-136 TDMA system, today ceased. Evolved EDGE, the latest revision, has peaks of 1 Mbit/s downstream and 400 kbit/s upstream, the Universal Mobile Telecommunications System, created and revised by the 3GPP. The family is a revision from GSM in terms of encoding methods and hardware
2.
Mobile phone
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A mobile phone is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the systems of a mobile phone operator. Most modern mobile telephone services use a network architecture, and, therefore. Mobile phones which offer these and more general computing capabilities are referred to as smartphones, the first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c.4.4 lbs. In 1983, the DynaTAC 8000x was the first commercially available mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to seven billion, penetrating 100% of the global population. In first quarter of 2016, the top smartphone manufacturers were Samsung, Apple, a handheld mobile radio telephone service was envisioned in the early stages of radio engineering. In 1917, Finnish inventor Eric Tigerstedt filed a patent for a pocket-size folding telephone with a thin carbon microphone. Early predecessors of cellular phones included analog radio communications from ships, the race to create truly portable telephone devices began after World War II, with developments taking place in many countries. These 0G systems were not cellular, supported few simultaneous calls, the first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c.4.4 lbs. The first commercial automated cellular network was launched in Japan by Nippon Telegraph and this was followed in 1981 by the simultaneous launch of the Nordic Mobile Telephone system in Denmark, Finland, Norway, and Sweden. Several other countries followed in the early to mid-1980s. These first-generation systems could support far more simultaneous calls but still used analog cellular technology, in 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. In 1991, the digital cellular technology was launched in Finland by Radiolinja on the GSM standard. This sparked competition in the sector as the new operators challenged the incumbent 1G network operators, ten years later, in 2001, the third generation was launched in Japan by NTT DoCoMo on the WCDMA standard. This was followed by 3. 5G, 3G+ or turbo 3G enhancements based on the high-speed packet access family, allowing UMTS networks to have data transfer speeds. By 2009, it had become clear that, at point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications. Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies
3.
GSM
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As of 2014 it has become the de facto global standard for mobile communications – with over 90% market share, operating in over 219 countries and territories. This expanded over time to include communications, first by circuit-switched transport, then by packet data transport via GPRS. Subsequently, the 3GPP developed third-generation UMTS standards followed by fourth-generation LTE Advanced standards, GSM is a trademark owned by the GSM Association. It may also refer to the most common voice codec used, the decision to develop a continental standard eventually resulted in a unified, open, standard-based network which was larger than that in the United States. In February 1987 Europe produced the very first agreed GSM Technical Specification, the MoU drew-in mobile operators from across Europe to pledge to invest in new GSM networks to an ambitious common date. In 1989, the Groupe Spécial Mobile committee was transferred from CEPT to the European Telecommunications Standards Institute, in parallel, France and Germany signed a joint development agreement in 1984 and were joined by Italy and the UK in 1986. In 1986 the European Commission proposed reserving the 900 MHz spectrum band for GSM, the former Finnish prime minister Harri Holkeri made the worlds first GSM call on July 1,1991, calling Kaarina Suonio using a network built by Telenokia and Siemens and operated by Radiolinja. In the following year,1992, saw the sending of the first short messaging service message, work began in 1991 to expand the GSM standard to the 1800 MHz frequency band and the first 1800 MHz network became operational in the UK by 1993 called and DCS1800. Also that year, Telecom Australia became the first network operator to deploy a GSM network outside Europe and the first practical hand-held GSM mobile phone became available. In 1995, fax, data and SMS messaging services were launched commercially, in the same year, the GSM Association formed. Pre-paid GSM SIM cards were launched in 1996 and worldwide GSM subscribers passed 100 million in 1998, in 2000 the first commercial GPRS services were launched and the first GPRS-compatible handsets became available for sale. In 2001 the first UMTS network was launched, a 3G technology that is not part of GSM, worldwide GSM subscribers exceeded 500 million. In 2002 the first Multimedia Messaging Service were introduced and the first GSM network in the 800 MHz frequency band became operational, EDGE services first became operational in a network in 2003 and the number of worldwide GSM subscribers exceeded 1 billion in 2004. By 2005, GSM networks accounted for more than 75% of the cellular network market. In 2005 the first HSDPA-capable network also became operational, the first HSUPA network launched in 2007. Worldwide GSM subscribers exceeded three billion in 2008, GSM is a second-generation standard employing time-division multiple-Access spectrum-sharing, issued by the European Telecommunications Standards Institute. GSM, for the first time, set a standard for Europe for wireless networks. It was also adopted by many countries outside Europe and this allowed subscribers to use other GSM networks that have roaming agreements with each other
4.
International Telecommunication Union
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ITU, based in Geneva, Switzerland, is a member of the United Nations Development Group. ITU has been an intergovernmental public-private partnership organization since its inception, ITU was formed in 1865, in Paris, at the International Telegraph Convention, this makes it one of the oldest intergovernmental organizations in the world. ITU became a United Nations specialized agency in 1947, the ITU comprises three sectors, each managing a different aspect of the matters handled by the Union, as well as ITU Telecom. The sectors were created during the restructuring of ITU at its 1992 Plenipotentiary Conference, radiocommunication Established in 1927 as the International Radio Consultative Committee or CCIR, this sector manages the international radio-frequency spectrum and satellite orbit resources. In 1992, the CCIR became the ITU-R, Standardization Standardization was the original purpose of ITU since its inception. Established in 1956 as the International Telephone and Telegraph Consultative Committee or CCITT, in 1993, the CCITT became the ITU-T. Development Established in 1992, this sector helps spread equitable, sustainable and affordable access to information and communication technologies, ITU Telecom ITU Telecom organizes major events for the worlds ICT community. A permanent General Secretariat, headed by the Secretary General, manages the work of the Union. The basic texts of the ITU are adopted by the ITU Plenipotentiary Conference, the ITU is headed by a Secretary-General, who is elected to a four-year term by the member states at the ITU Plenipotentiary Conference. On 23 October 2014 Houlin Zhao was elected 19th Secretary-General of the ITU at the Plenipotentiary Conference in Busan and his four-year mandate started on 1 January 2015, and he was formally inaugurated on 15 January 2015. There are 193 Member States of the ITU, which are all UN member states, the most recent member state to join the ITU is South Sudan, which became a member on 14 July 2011. The Republic of China was blocked from membership by the Peoples Republic of China, palestine was admitted as an observer in 2010. The Summit was held as two conferences in 2003 and 2005 in Geneva and Tunis, respectively, with the aim of bridging the digital divide, in December 2012, the ITU facilitated The World Conference on International Telecommunications 2012 in Dubai. WCIT-12 was a conference to address International Telecommunications Regulations, the international rules for telecommunications. The previous conference to update the Regulations was held in Melbourne in 1988, in August 2012, ITU called for a public consultation on a draft document ahead of the conference. Telecommunications ministers from 193 countries attended the conference in Dubai, the current regulatory structure was based on voice telecommunications, when the Internet was still in its infancy. In 1988, telecommunications operated under regulated monopolies in most countries, as the Internet has grown, organizations such as ICANN have come into existence to manage key resources such as Internet addresses and Domain Names. Some outside the United States believe that the United States exerts too much influence over the governance of the Internet, current proposals look to take into account the prevalence of data communications
5.
General Packet Radio Service
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General Packet Radio Service is a packet oriented mobile data service on the 2G and 3G cellular communication systems global system for mobile communications. GPRS was originally standardized by European Telecommunications Standards Institute in response to the earlier CDPD and it is now maintained by the 3rd Generation Partnership Project. GPRS usage is typically charged based on volume of data transferred, contrasting with circuit switched data, sometimes billing time is broken down to every third of a minute. Usage above the cap is charged per megabyte, speed limited. In 2G systems, GPRS provides data rates of 56–114 kbit/second, 2G cellular technology combined with GPRS is sometimes described as 2. 5G, that is, a technology between the second and third generations of mobile telephony. It provides moderate-speed data transfer, by using unused time division multiple access channels in, for example, GPRS is integrated into GSM Release 97 and newer releases. The GPRS core network allows 2G, 3G and WCDMA mobile networks to transmit IP packets to external networks such as the Internet, the GPRS system is an integrated part of the GSM network switching subsystem. This is much faster using the ordinary SMS over GSM. GPRS supports the protocols, Internet Protocol. In practice, built-in mobile browsers use IPv4 since IPv6 was not yet popular, in this mode PPP is often not supported by the mobile phone operator but if the mobile is used as a modem to the connected computer, PPP is used to tunnel IP to the phone. This allows an IP address to be assigned dynamically to the mobile equipment and this is typically used for applications like wireless payment terminals, although it has been removed from the standard. When TCP/IP is used, each phone can have one or more IP addresses allocated, GPRS will store and forward the IP packets to the phone even during handover. The TCP handles any packet loss, devices supporting GPRS are divided into three classes, Class A Can be connected to GPRS service and GSM service, using both at the same time. Such devices are known to be available today, Class B Can be connected to GPRS service and GSM service, but using only one or the other at a given time. During GSM service, GPRS service is suspended, and then resumed automatically after the GSM service has concluded, most GPRS mobile devices are Class B. Class C Are connected to either GPRS service or GSM service, must be switched manually between one or the other service. A true Class A device may be required to transmit on two different frequencies at the time, and thus will need two radios. To get around this requirement, a GPRS mobile may implement the dual transfer mode feature
6.
Enhanced Data Rates for GSM Evolution
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Enhanced Data rates for GSM Evolution is a digital mobile phone technology that allows improved data transmission rates as a backward-compatible extension of GSM. EDGE is considered a pre-3G radio technology and is part of ITUs 3G definition, EDGE was deployed on GSM networks beginning in 2003 – initially by Cingular in the United States. EDGE is standardized also by 3GPP as part of the GSM family, a variant, so called Compact-EDGE, was developed for use in a portion of Digital AMPS network spectrum. EDGE can be used for any packet switched application, such as an Internet connection, Evolved EDGE continues in Release 7 of the 3GPP standard providing reduced latency and more than doubled performance e. g. to complement High-Speed Packet Access. Peak bit-rates of up to 1 Mbit/s and typical bit-rates of 400 kbit/s can be expected, eDGE/EGPRS is implemented as a bolt-on enhancement for 2. 5G GSM/GPRS networks, making it easier for existing GSM carriers to upgrade to it. EDGE is a superset to GPRS and can function on any network with GPRS deployed on it, EDGE requires no hardware or software changes to be made in GSM core networks. EDGE-compatible transceiver units must be installed and the base station needs to be upgraded to support EDGE. If the operator already has this in place, which is often the case today, today EDGE is supported by all major chip vendors for both GSM and WCDMA/HSPA. In addition to Gaussian minimum-shift keying, EDGE uses higher-order PSK/8 phase shift keying for the five of its nine modulation. EDGE produces a 3-bit word for every change in carrier phase and this effectively triples the gross data rate offered by GSM. It introduces a new technology not found in GPRS, Incremental Redundancy and this increases the probability of correct decoding. EDGE can carry a bandwidth up to 236 kbit/s for 4 timeslots in packet mode and this means it can handle four times as much traffic as standard GPRS. EDGE meets the International Telecommunications Unions requirement for a 3G network and it also enhances the circuit data mode called HSCSD, increasing the data rate of this service. In GPRS, the Coding Schemes CS-1 to CS-4 specify the number of parity bits generated by the cyclic code, in GPRS Coding Schemes CS-1 through CS-3, the convolutional code is of rate 1/2, i. e. each input bit is converted into two coded bits. In Coding Schemes CS-2 and CS-3, the output of the code is punctured to achieve the desired code rate. In GPRS Coding Scheme CS-4, no coding is applied. In EGPRS/EDGE, the Modulation and Coding Schemes MCS-1 to MCS-9 take the place of the Coding Schemes of GPRS, MCS-1 through MCS-4 use GMSK and have performance similar to GPRS, while MCS-5 through MCS-9 use 8PSK. In all EGPRS Modulation and Coding Schemes, a code of rate 1/3 is used
7.
UMTS
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The Universal Mobile Telecommunications System is a third generation mobile cellular system for networks based on the GSM standard. UMTS uses wideband code division multiple access radio access technology to offer greater spectral efficiency, UMTS specifies a complete network system, which includes the radio access network, the core network and the authentication of users via SIM cards. The technology described in UMTS is sometimes referred to as Freedom of Mobile Multimedia Access or 3GSM. Unlike EDGE and CDMA2000, UMTS requires new base stations and new frequency allocations, UMTS supports maximum theoretical data transfer rates of 42 Mbit/s when Evolved HSPA is implemented in the network. Users in deployed networks can expect a transfer rate of up to 384 kbit/s for Release 99 handsets, since 2006, UMTS networks in many countries have been or are in the process of being upgraded with High-Speed Downlink Packet Access, sometimes known as 3. 5G. Currently, HSDPA enables downlink transfer speeds of up to 21 Mbit/s, work is also progressing on improving the uplink transfer speed with the High-Speed Uplink Packet Access. The first national consumer UMTS networks launched in 2002 with a emphasis on telco-provided mobile applications such as mobile TV. UMTS combines three different terrestrial air interfaces, GSMs Mobile Application Part core, and the GSM family of speech codecs, the air interfaces are called UMTS Terrestrial Radio Access. All air interface options are part of ITUs IMT-2000, in the currently most popular variant for cellular mobile telephones, W-CDMA is used. Please note that the terms W-CDMA, TD-CDMA and TD-SCDMA are misleading, while they suggest covering just a channel access method, they are actually the common names for the whole air interface standards. W-CDMA or WCDMA, along with UMTS-FDD, UTRA-FDD, or IMT-2000 CDMA Direct Spread is an air interface found in 3G mobile telecommunications networks. W-CDMA uses the DS-CDMA channel access method with a pair of 5 MHz wide channels, in contrast, the competing CDMA2000 system uses one or more available 1.25 MHz channels for each direction of communication. W-CDMA systems are criticized for their large spectrum usage, which delayed deployment in countries that acted relatively slowly in allocating new frequencies specifically for 3G services. The specific frequency bands originally defined by the UMTS standard are 1885–2025 MHz for the mobile-to-base, in the US, 1710–1755 MHz and 2110–2155 MHz are used instead, as the 1900 MHz band was already used. Some carriers such as T-Mobile use band numbers to identify the UMTS frequencies, in the late 1990s, W-CDMA was developed by NTT DoCoMo as the air interface for their 3G network FOMA. Later NTT DoCoMo submitted the specification to the International Telecommunication Union as a candidate for the international 3G standard known as IMT-2000. The ITU eventually accepted W-CDMA as part of the IMT-2000 family of 3G standards, as an alternative to CDMA2000, EDGE, later, W-CDMA was selected as an air interface for UMTS. As NTT DoCoMo did not wait for the finalisation of the 3G Release 99 specification, however, this has been resolved by NTT DoCoMo updating their network
8.
High Speed Packet Access
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A further improved 3GPP standard, Evolved High Speed Packet Access, was released late in 2008 with subsequent worldwide adoption beginning in 2010. The newer standard allows bit-rates to reach as high as 337 Mbit/s in the downlink and 34 Mbit/s in the uplink, however, these speeds are rarely achieved in practice. The first HSPA specifications supported increased peak data rates of up to 14 Mbit/s in the downlink and 5.76 Mbit/s in the uplink. It also reduced latency and provided up to five times more capacity in the downlink. HSDPA has been introduced with 3GPP Release 5, which accompanies a improvement on the uplink providing a new bearer of 384 kbit/s. The previous maximum bearer was 128 kbit/s, as well as improving data rates, HSDPA also decreases latency and so the round trip time for applications. HSPA+ introduced in 3GPP Release 7 further increases data rates by adding 64QAM modulation, MIMO and Dual-Cell HSDPA operation, even higher speeds of up to 337.5 Mbit/s are possible with Release 11 of the 3GPP standards. The first phase of HSDPA has been specified in the 3GPP release 5, phase one introduces new basic functions and is aimed to achieve peak data rates of 14.0 Mbit/s with significantly reduced latency. The improvement in speed and latency reduces the cost per bit, further new features are the High Speed Downlink Shared Channels, the adaptive modulation QPSK and 16QAM and the High Speed Medium Access protocol in base station. The upgrade to HSDPA is often just an update for WCDMA networks. In general voice calls are prioritized over data transfer. The following table is derived from table 5. 1a of the release 11 of 3GPP TS25.306 and shows maximum data rates of different device classes and by what combination of features they are achieved. The per-cell per-stream data rate is limited by the Maximum number of bits of an HS-DSCH transport block received within an HS-DSCH TTI, so for example Cat 10 can decode 27952 bits/2 ms =13.976 MBit/s. Categories 1-4 and 11 have inter-TTI intervals of 2 or 3, Dual-Cell and MIMO 2x2 each multiply the maximum data rate by 2, because multiple independent transport blocks are transmitted over different carriers or spatial streams, respectively. The data rates given in the table are rounded to one decimal point, further UE categories were defined from 3GGP Release 7 onwards as Evolved HSPA and are listed in Evolved HSDPA UE Categories. Notes, As of 28 August 2009,250 HSDPA networks have commercially launched mobile services in 109 countries. 169 HSDPA networks support 3.6 Mbit/s peak downlink data throughput, a growing number are delivering 21 Mbit/s peak data downlink and 28 Mbit/s. CDMA2000-EVDO networks had the lead on performance, and Japanese providers were highly successful benchmarks for it
9.
LTE (telecommunication)
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In telecommunication, Long-Term Evolution is a standard for high-speed wireless communication for mobile phones and data terminals, based on the GSM/EDGE and UMTS/HSPA technologies. It increases the capacity and speed using a different radio interface together with core network improvements, the standard is developed by the 3GPP and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is the path for carriers with both GSM/UMTS networks and CDMA2000 networks. The different LTE frequencies and bands used in different countries mean that only multi-band phones are able to use LTE in all countries where it is supported. LTE is commonly marketed as 4G LTE, but it does not meet the criteria of a 4G wireless service, as specified in the 3GPP Release 8 and 9 document series. The requirements were set forth by the ITU-R organization in the IMT Advanced specification. The LTE Advanced standard formally satisfies the ITU-R requirements to be considered IMT-Advanced, to differentiate LTE Advanced and WiMAX-Advanced from current 4G technologies, ITU has defined them as True 4G. LTE stands for Long Term Evolution and is a trademark owned by ETSI for the wireless data communications technology. However, other nations and companies do play an role in the LTE project. The goal of LTE was to increase the capacity and speed of data networks using new DSP techniques. A further goal was the redesign and simplification of the architecture to an IP-based system with significantly reduced transfer latency compared to the 3G architecture. The LTE wireless interface is incompatible with 2G and 3G networks, LTE was first proposed by NTT DoCoMo of Japan in 2004, and studies on the new standard officially commenced in 2005. Initially, CDMA operators planned to upgrade to rival standards called UMB and WiMAX, the evolution of LTE is LTE Advanced, which was standardized in March 2011. Services are expected to commence in 2013, additional evolution known as LTE Advanced Pro have been approved in year 2015. The LTE specification provides downlink peak rates of 300 Mbit/s, uplink peak rates of 75 Mbit/s, LTE has the ability to manage fast-moving mobiles and supports multi-cast and broadcast streams. LTE supports scalable carrier bandwidths, from 1.4 MHz to 20 MHz, the simpler architecture results in lower operating costs. In 2004, NTT DoCoMo of Japan proposes LTE as the international standard, in September 2006, Siemens Networks showed in collaboration with Nomor Research the first live emulation of an LTE network to the media and investors. As live applications two users streaming an HDTV video in the downlink and playing a game in the uplink have been demonstrated
10.
4G
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4G is the fourth generation of wireless mobile telecommunications technology, succeeding 3G. A 4G system must provide capabilities defined by ITU in IMT Advanced, potential and current applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, and 3D television. The first-release Long Term Evolution standard has been deployed in Oslo, Norway. It has, however, been debated whether first-release versions should be considered 4G, since the first-release versions of Mobile WiMAX and LTE support much less than 1 Gbit/s peak bit rate, they are not fully IMT-Advanced compliant, but are often branded 4G by service providers. According to operators, a generation of the network refers to the deployment of a new non-backward-compatible technology, as opposed to earlier generations, a 4G system does not support traditional circuit-switched telephony service, but all-Internet Protocol based communication such as IP telephony. The peak bit rate is improved by smart antenna arrays for multiple-input multiple-output communications. New mobile generations have appeared about ten years since the first move from 1981 analog to digital transmission in 1992. In the mid-1990s, the ITU-R standardization organization released the IMT-2000 requirements as a framework for what standards should be considered 3G systems, in 2008, ITU -R specified the IMT - Advanced requirements for 4G systems. In theory speeds up to 672 Mbit/s are possible, but have not been deployed yet, the fastest 3G-based standard in the CDMA2000 family is the EV-DO Rev. B, which is available since 2010 and offers 15.67 Mbit/s downstream. This article refers to 4G using IMT-Advanced, as defined by ITU-R, an IMT-Advanced cellular system must fulfill the following requirements, Be based on an all-IP packet switched network. Have peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access, be able to dynamically share and use the network resources to support more simultaneous users per cell. Use scaleable channel bandwidths of 5–20 MHz, optionally up to 40 MHz. Rumney, IMT-Advanced, 4G Wireless Takes Shape in an Olympic Year. Have peak link spectral efficiency of 15-bit/s/Hz in the downlink, and 6. 75-bit/s/Hz in the up link, system spectral efficiency is, in indoor cases, 3-bit/s/Hz/cell for downlink and 2. 25-bit/s/Hz/cell for up link. In September 2009, the proposals were submitted to the International Telecommunication Union as 4G candidates. Basically all proposals are based on two technologies, LTE Advanced standardized by the 3GPP802. The latters standard versions were ratified in spring 2011, but are far from being implemented. The first set of 3GPP requirements on LTE Advanced was approved in June 2008, LTE Advanced was to be standardized in 2010 as part of Release 10 of the 3GPP specification. LTE Advanced will be based on the existing LTE specification Release 10, a summary of the technologies that have been studied as the basis for LTE Advanced is included in a technical report
11.
IP Multimedia Subsystem
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The IP Multimedia Subsystem or IP Multimedia Core Network Subsystem is an architectural framework for delivering IP multimedia services. Historically, mobile phones have provided voice call services over a switched-circuit-style network, alternative methods of delivering voice or other multimedia services over IP have become available on smartphones, but they have not become standardized across the industry. IMS is a framework to provide such standardization. IMS was originally designed by the wireless standards body 3rd Generation Partnership Project and its original formulation represented an approach to delivering Internet services over GPRS. This vision was later updated by 3GPP, 3GPP2 and ETSI TISPAN by requiring support of other than GPRS, such as Wireless LAN, CDMA2000. To ease the integration with the Internet, IMS uses IETF protocols wherever possible and this is done by having a horizontal control layer that isolates the access network from the service layer. From a logical perspective, services need not have their own control functions. However, in implementation this does not necessarily map into greater reduced cost, alternative and overlapping technologies for access and provisioning of services across wired and wireless networks include combinations of Generic Access Network, soft switches and naked SIP. Since it is becoming easier to access content and contacts using mechanisms outside the control of traditional wireless/fixed operators. Examples of global standards based on IMS are MMTel which is the basis for Voice over LTE, IMS was originally defined by an industry forum called 3G. IP, formed in 1999. 3G. IP developed the initial IMS architecture, which was brought to the 3rd Generation Partnership Project and it first appeared in Release 5, when SIP-based multimedia was added. Support for the older GSM and GPRS networks was also provided, 3GPP2 based their CDMA2000 Multimedia Domain on 3GPP IMS, adding support for CDMA2000. AGCF works as a bridge interconnecting the IMS networks and the Megaco/H.248 networks, Megaco/H.248 networks offers the possibility to connect terminals of the old legacy networks to the new generation of networks based on IP networks. AGCF acts a SIP User agent towards the IMS and performs the role of P-CSCF, SIP User Agent functionality is included in the AGCF, and not on the customer device but in the network itself. 3GPP release 8 added support for LTE / SAE, multimedia session continuity, enhanced emergency sessions, 3GPP release 9 added support for IMS emergency calls over GPRS and EPS, enhancements to multimedia telephony, IMS media plane security, enhancements to services centralization and continuity. 3GPP release 10 added support for inter device transfer, enhancements to the radio voice call continuity. 3GPP release 11 added USSD simulation service, network-provided location information for IMS, SMS submit and delivery without MSISDN in IMS, each of the functions in the diagram is explained below. The IP multimedia core network subsystem is a collection of different functions, linked by standardized interfaces, a function is not a node, An implementer is free to combine two functions in one node, or to split a single function into two or more nodes
12.
CdmaOne
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Interim Standard 95 was the first ever CDMA-based digital cellular technology. It was developed by Qualcomm and later adopted as a standard by the Telecommunications Industry Association in TIA/EIA/IS-95 release published in 1995, the proprietary name for IS-95 is cdmaOne. It is a 2G mobile telecommunications standard that uses CDMA, an access scheme for digital radio, to send voice, data. CDMA or code division multiple access is a radio system that transmits streams of bits. CDMA permits several radios to share the same frequencies, unlike TDMA time division multiple access, a competing system used in 2G GSM, all radios can be active all the time, because network capacity does not directly limit the number of active radios. In North America, the technology competed with Digital AMPS and it is now being supplanted by IS-2000, a later CDMA-based standard. CdmaOnes technical history is reflective of both its birth as a Qualcomm internal project, and the world of then-unproven competing digital cellular standards under which it was developed, the term IS-95 generically applies to the earlier set of protocol revisions, namely P_REVs one through five. P_REV=1 was developed under an ANSI standards process with documentation reference J-STD-008, J-STD-008, published in 1995, was only defined for the then-new North American PCS band. The term IS-95 properly refers to P_REV=1, developed under the Telecommunications Industry Association standards process, IS-95 offered interoperation with the analog cellular network. For digital operation, IS-95 and J-STD-008 have most technical details in common, the immature style and structure of both documents are highly reflective of the standardizing of Qualcomms internal project. P_REV=2 is termed Interim Standard 95A, IS-95A was developed for Band Class 0 only, as in incremental improvement over IS-95 in the TIA standards process. P_REV=3 is termed Technical Services Bulletin 74, tSB-74 was the next incremental improvement over IS-95A in the TIA standards process. P_REV=4 is termed Interim Standard 95B Phase I, and P_REV=5 is termed Interim Standard 95B Phase II, p_REV=4 was by far the most popular variant of IS-95, with P_REV=5 only seeing minimal uptake in South Korea. P_REV=6 and beyond fall under the CDMA2000 umbrella, besides technical improvements, the IS-2000 documents are much more mature in terms of layout and content. They also provide backwards-compatibility to IS-95, the IS-95 standards describe an air interface, a set of protocols used between mobile units and the network. IS-95 defines the transmission of signals in both the forward and reverse directions, in the forward direction, radio signals are transmitted by base stations. Every BTS is synchronized with a GPS receiver so transmissions are tightly controlled in time, all forward transmissions are QPSK with a chip rate of 1,228,800 per second. Each signal is spread with a Walsh code of length 64, for the reverse direction, radio signals are transmitted by the mobile
13.
CDMA2000
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CDMA2000 is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a successor to second-generation cdmaOne set of standards and used especially in North America. CDMA2000 compares to UMTS, a set of 3G standards, which is developed by 3GPP and used in Europe, Japan. The name CDMA2000 denotes a family of standards that represent the successive and these are, Voice, CDMA2000 1xRTT, 1X Advanced Data, CDMA2000 1xEV-DO, Release 0, Revision A, Revision B, Ultra Mobile Broadband All are approved radio interfaces for the ITUs IMT-2000. In the United States, CDMA2000 is a trademark of the Telecommunications Industry Association. CDMA2000 1X, also known as 1x and 1xRTT, is the core CDMA2000 wireless air interface standard, the designation 1x, meaning 1 times Radio Transmission Technology, indicates the same radio frequency bandwidth as IS-95, a duplex pair of 1.25 MHz radio channels. 1xRTT almost doubles the capacity of IS-95 by adding 64 more traffic channels to the forward link, the 1X standard supports packet data speeds of up to 153 kbit/s with real world data transmission averaging 80–100 kbit/s in most commercial applications. IMT-2000 also made changes to the link layer for greater use of data services, including medium and link access control protocols. The IS-95 data link layer only provided best efforts delivery for data, CDMA2000 1xEV-DO, often abbreviated as EV-DO or EV, is a telecommunications standard for the wireless transmission of data through radio signals, typically for broadband Internet access. It uses multiplexing techniques including code division multiple access as well as time division multiple access to both individual users throughput and the overall system throughput. 1X Advanced is the evolution of CDMA2000 1X and it provides up to four times the capacity and 70% more coverage compared to 1X. The CDMA Development Group states that, as of April 2014, the intended 4G successor to CDMA2000 was UMB, however, in November 2008, Qualcomm announced it was ending development of the technology, favoring LTE instead
14.
ETSI
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ETSI produces globally-applicable standards for Information and Communications Technologies, including fixed, mobile, radio, converged, broadcast and internet technologies. ETSI was created by CEPT in 1988 and is recognized by the European Commission. Based in Sophia Antipolis, ETSI is officially responsible for standardization of Information and Communication Technologies within Europe, ETSI publishes between 2,000 and 2,500 standards every year. Since its establishment in 1988, it produced over 30,000, ETSI inspired the creation of, and is a partner in, 3GPP and oneM2M. The work of a single Technical Committee may be represented in several clusters, clusters facilitate easy identification of an area of interest based on business relevance or application domain rather than purely on specific technical work areas. In 2013, ETSIs budget exceeded €23 million, with coming from members, commercial activities like sale of documents, plug-tests and fora hosting, contract work. ETSI is a partner organization of the Global Standards Collaboration initiative. Nearly a third of ETSIs members are Small and Medium Enterprises, a list of current members can be found here. ETSI Standard, Used when the document contains normative requirements and it is necessary to submit the document to the whole ETSI membership for approval. ETSI Guide, Used when the document contains guidance on handling of technical standardization activities, special Report, Used for various purposes, including giving public availability to information not produced within a technical committee. ETSI SRs are also used for documents, e. g. documents that are dynamically generated by a query to a database via the web. An SR is published by the committee in which it was produced. ETSI Technical Report, Used when the document contains mainly informative elements, ETSI Group Specification, Used by Industry Specification Groups according to the decision making procedures defined in the groups Terms of Reference. This deliverable type is approved and adopted by the Industry Specification Group that drafted it and this list is gathered from the European Telecommunications Standards Institute website. All technical committees, working and industry groups are accessible via the ETSI Portal Embedded Common Interface ETSI Official Website ETSI Portal Small Business Standards aisbl
15.
Sophia Antipolis
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Sophia Antipolis is a leading European technology park. Much of the park falls within the commune of Valbonne, which lies northwest of Antibes, created in 1970-1984, it houses primarily companies in the fields of computing, electronics, pharmacology and biotechnology. Several institutions of learning are also located here, along with the European headquarters of W3C. In the early years, one of the challenges of Sophia Antipolis was to relate people. The Human Factor is what was to distinguish the Science and Technology Park in the world as a landmark of science, invention, innovation and it was to focus on building an international environment, creating an international community. This means taking into account and improving tenant interaction, networking, the concept was that bringing together people from different intellectual horizons and making them meet, would bring added value and generate innovation. Many professional clubs were thus launched, The Sophia business angels club, many of the roads within the technology park have Greek names. There is a giant sculptured Greek urn as a centre-piece on one of the roundabouts, the residential community of Garbejaire is located within the technology park. There is a park with a play area for children. There is also a large communal corporate dining facility that is shared by several companies on the periphery of Garbejaire, several bus routes run through the technology park. There is a bus station with a ticket office. The company who runs the lines is called Envibus. fr, one of the bus routes to Antibes goes directly to Antibes railway station which provides access to the Riviera coastal railway. The station is served by trains to Nice and Monaco or westbound to Toulon. The nearest international airport is in Nice, there is a large national park around the technology park and several large villages on the outskirts of this park. Wild boar live within the park and occasionally walk through the technology park, there is a large community of small bats that become active as soon as it starts to get dark. It is possible to attract the attention of the bats which respond to mimicry, cotedAzur Directory of Organizations for Sophia Antipolis Sophia Antipolis Foundation Sophia Antipolis Economic Development Sophia Antipolis Urban Community Centre International de Valbonne
16.
Nortel
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It was founded in Montreal, Quebec in 1895 as the Northern Electric and Manufacturing Company. At its height, Nortel accounted for more than a third of the valuation of all the companies listed on the Toronto Stock Exchange. Nortel had filed for protection from its creditors in the United States, Canada, in June 2009, the company announced it would cease operations and sell off all of its business units. The period of protection was extended to February 2,2013. As part of the proceedings in the United States, Nortel Networks Inc. publishes monthly operating reports outlining cash receipts and disbursements. By 2016 Nortel had sold billions of dollars worth of assets and he later refined its design at Brantford after producing his first working prototype in Boston. In addition to phones, four years later, the department started manufacturing its first switchboard, the small manufacturing department expanded yearly with the growth and popularity of the telephone to 50 employees in 1888. By 1890 it had transformed into its own branch of operations with 200 employees. As the manufacturing branch expanded, its production ability increased beyond the demand for phones and this was a problem because the Bell Telephone Company of Canadas charter would not allow them to build other products. This company was incorporated as the Northern Electric and Manufacturing Company Limited, Northern Electric and Manufacturing Company Limited was incorporated on 7 December 1895, by the following corporate members, Charles Fleetford Sise Sr. McFarlane, manager, all of the city and district of Montreal, the initial stock capital was $50,000 at $100 per share, with 93 percent held by the Bell Telephone Company of Canada and the remainder held by the seven corporate members above. The first general meeting was held on March 24,1896. In December 1899, The Bell Telephone Company of Canada bought a company for $500,000. Northern Electric and Manufacturing further expanded its line in 1900. In 1911 the Wire and Cable company changed its name to the Imperial Wire, the construction of a new manufacturing plant started in 1913 at Shearer Street in Montreal, Canada, as preparations began for the two manufacturing companies integration. This facility at Shearer Street was the manufacturing centre until the mid-1950s. Edward Fleetford Sise was the president and his brother Paul Fleetford Sise was the vice-president, during the First World War Northern Electric manufactured the Portable Commutator, a one-wire telegraphic switchboard for military operations in the field. In 1922, Northern started to produce, for $5, the Peanut vacuum tube, the use of alternating current was still under development during this time
17.
AT&T Mobility
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AT&T Mobility is the second largest wireless telecommunications provider in the United States and Puerto Rico behind Verizon Wireless. Cingular became wholly owned by AT&T in December 2006 as a result of AT&Ts acquisition of BellSouth, in January 2007, Cingular confirmed it would re-brand itself under the AT&T name. The transition concluded in late June, just prior to the rollout of the Apple iPhone, on March 20,2011, AT&T Mobility announced its intention to acquire T-Mobile USA from Deutsche Telekom for $39 billion. If it had received government and regulatory approval, AT&T would have had more than 130 million subscribers, in December 2011, in the face of both governmental and widespread consumer opposition, AT&T withdrew their offer to complete the merger. Beginning in July 2007, AT&T allows its AT&T Unity plan users to have Rollover, AT&T also launched video share in 2007, in which a mobile caller can stream live video from one phone to another over the 3G network with video share capable phones. This allows one mobile phone user to view video from another users camera through the phone in real time. AT&T also had A-list, similar to former competitor Alltels program launched on April 20,2006 branded My Circle, AT&T rolled out the A-list program on September 20,2009. Customers with individual Nation plans of $59, FamilyTalk customers with plans of $89.99 or more could select up to ten numbers which any person in the FamilyTalk plan can call as much as they want. Effective September 1,2011, the A-List feature is no longer available to new consumer, existing customers who had A-List on their account prior to September 1,2011, are able to keep the feature as long as they stay on a qualifying rate plan. As of October 25,2013 AT&T no longer offers Nation Plans or Family Talk Plans to its new customers. New customers are now required to have one of AT&T Mobile Share Value plans which include unlimited Talk, Text, as of January 8,2016 AT&T no longer offers 2 year contracts for subsidized smart phones to its consumer customers. Customers who currently have 2 year contracts are grandfathered, until they upgrade to a new device they will have to choose from AT&Ts NEXT installment plans for smartphones, AT&T has also reintroduced unlimited data plans for its customers who also have either AT&T U-verse or AT&Ts newly acquired DirecTV. Unlimited data plans may be speed throttled after 22 GB of data have been used, with the inclusion of these new plans AT&T has also introduced a free roaming in Mexico feature for its postpaid customers. Within AT&Ts 21-state landline footprint, other AT&T services are offered at the AT&T retail stores, including signing up for home phone, internet, a large number of AT&T Mobility employees are unionized, belonging to the Communications Workers of America. The CWA represented roughly 15,000 of the previous 20,000 formerly AT&T Wireless employees as of early 2006, as of the end of 2009, the CWA website claims roughly 40,000 workers of AT&T Mobility are represented by the union. Cingular Wireless was founded in 2000 as a joint venture of SBC Communications, the joint venture created the nations second-largest carrier. Cingular grew out of a conglomeration of more than 100 companies, Cingulars lineage can be traced back to Advanced Mobile Phone Service, which was a subsidiary of AT&T created in 1978 to provide cellular service nationwide. AMPS was divided among the Regional Bell Operating Companies as part of the Bell System divestiture, with the exception of Pacific Bell and BellSouth Mobility DCS, the digital network consisted of D-AMPS technology
18.
Bell Northern Research
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Bell-Northern Research was a telecommunications research and development company established In 1971 when Bell Canada and Northern Electric combined their R&D organizations. It was jointly owned by Bell Canada and Northern Telecom, BNR was absorbed into Nortel Networks when that company changed its name from Northern Telecom in the mid-1990s. Bell-Northern Research pioneered the development of technology, and created the first practical digital PBX. Under the direction of then Nortel Chief Officer, John Roth, BNR lost its identity in the 1990s. For much of its history, Bell Canada operated as the Canadian division of the Bell System. Northern Electric spun off a subsidiary in 1934, Dominion Sound Equipment, over time, the division evolved in an attempt to use its design talent and manufacturing ability on third party projects. In 1937, this became the Special Products Division. For many years the SPD was used as Bell Canadas R&D arm, although as before, in 1949, the United States Justice department attempted to force AT&T to divest itself of its Western Electric subsidiary. As a result of legal action, Western Electric sold its shares in Northern Electric to Bell Canada. In 1957, Northern Electric started its own research and development labs in Belleville, two years later, Northern Electric created the Northern Electric Research and Development Laboratories in Ottawa. In 1971, Bell Canada and Northern Electric combined their R&D organizations, bNRs researchers pioneered the view that a telephone switch was best regarded as a special form of real-time computer, a view that was considered to be highly innovative in the 1970s. In the 1960s, however, this view was coming under a deal of strain. Increasingly, telephone users wanted to call, forward, and record voice greetings. Such features required more flexibility in the controller, leading to the development of computer-controlled switching machines, Northern Electric introduced its first electronic central office system in 1969 with the SP1. The SP1 had a fully computer-based electronic control system, thus the name SP and its switching matrix was still electromechanical. Rather than the reed relay matrix of the 1ESS, it used the minibar, BNR was, with Northern Telecom, a part owner of MicroSystems International a semiconductor manufacturer based in Kanata, outside Ottawa. BNR introduced the Meridian SL-1 in 1975, the worlds first all-digital PABX aimed at medium-sized businesses, the SL-1 was fully digital in both control and switching. As such the SL-1 was smaller, much more reliable, the SL-1 design evolved into Meridian-1, and subsequently the CS1000x as Nortels private network flagship offering
19.
Internet Protocol
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The Internet Protocol is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet, IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered and it also defines addressing methods that are used to label the datagram with source and destination information. The Internet protocol suite is often referred to as TCP/IP. The first major version of IP, Internet Protocol Version 4, is the dominant protocol of the Internet and its successor is Internet Protocol Version 6. The Internet Protocol is responsible for addressing hosts and for routing datagrams from a source host to a destination host across one or more IP networks. For this purpose, the Internet Protocol defines the format of packets, each datagram has two components, a header and a payload. The IP header is tagged with the source IP address, the destination IP address, the payload is the data that is transported. This method of nesting the data payload in a packet with a header is called encapsulation, IP addressing entails the assignment of IP addresses and associated parameters to host interfaces. The address space is divided into networks and subnetworks, involving the designation of network or routing prefixes, IP routing is performed by all hosts, as well as routers, whose main function is to transport packets across network boundaries. Routers communicate with one another via specially designed routing protocols, either interior gateway protocols or exterior gateway protocols, IP routing is also common in local networks. For example, many Ethernet switches support IP multicast operations and these switches use IP addresses and Internet Group Management Protocol to control multicast routing but use MAC addresses for the actual routing. The versions currently relevant are IPv4 and IPv6, in May 1974, the Institute of Electrical and Electronic Engineers published a paper entitled A Protocol for Packet Network Intercommunication. The papers authors, Vint Cerf and Bob Kahn, described a protocol for sharing resources using packet switching among network nodes. A central control component of this model was the Transmission Control Program that incorporated both connection-oriented links and datagram services between hosts, the model became known as the Department of Defense Internet Model and Internet protocol suite, and informally as TCP/IP. IP versions 0 to 3 were experimental versions, used between 1977 and 1979, IEN26, dated February 1978 describes a version of the IP header that uses a 1-bit version field. IEN28, dated February 1978 describes IPv2, IEN41, dated June 1978 describes the first protocol to be called IPv4. The IP header is different from the modern IPv4 header, IEN44, dated June 1978 describes another version of IPv4, also with a header different from the modern IPv4 header
20.
BT Group
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BT Group plc is a holding company which owns British Telecommunications plc, a British multinational telecommunications services company with head offices in London, United Kingdom. It has operations in around 180 countries, BTs origins date back to the founding of the Electric Telegraph Company in 1846 which developed a nationwide communications network. In 1912, the General Post Office, a government department, the Post Office Act of 1969 led to the GPO becoming a public corporation. British Telecommunications, trading as British Telecom, was formed in 1980, British Telecommunications was privatised in 1984, becoming British Telecommunications plc, with some 50 percent of its shares sold to investors. The Government sold its stake in further share sales in 1991 and 1993. BT has a listing on the London Stock Exchange, a secondary listing on the New York Stock Exchange. BT controls a number of large subsidiaries, BT announced in February 2015 that it had agreed to acquire EE for £12.5 billion, and received final regulatory approval from the Competition and Markets Authority on 15 January 2016. The transaction was completed on 29 January 2016, BTs origins date back to the establishment of the first telecommunications companies in Britain. Among them was the first commercial service, the Electric Telegraph Company. As these companies amalgamated and were taken over or collapsed, the companies were transferred to state control under the Post Office in 1912. These companies were merged and rebranded as British Telecom, in January 1878 Alexander Graham Bell demonstrated his recently developed telephone to Queen Victoria at Osborne House on the Isle of Wight. John Hudson, with his premises in nearby Shudehill. As the number of installed telephones across the country grew it became sensible to consider constructing telephone exchanges to allow all the telephones in each city to be connected together, the first exchange was opened in London in August 1879, closely followed by the Lancashire Telephonic Exchange in Manchester. From 1878, the service in Britain was provided by private sector companies such as the National Telephone Company. In 1896, the National Telephone Company was taken over by the General Post Office, in 1912 it became the primary supplier of telecommunications services, after the Post Office took over the private sector telephone service in GB, except for a few local authority services. Those services all folded within a few years, the exception being Kingston upon Hull. Converting the Post Office into an industry, as opposed to a governmental department, was first discussed in 1932 by Lord Wolmer. In 1932 the Bridgeman Committee produced a report that was rejected, in 1961, more proposals were ignored
21.
Orange S.A.
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Orange S. A. formerly France Télécom S. A. is a French multinational telecommunications corporation. It has 256 million customers worldwide and employs 95,000 people in France, in 2015, the group had revenue of €40 billion. The companys head office is located in the 15th arrondissement of Paris, the current CEO is Stéphane Richard. The company is a component of the Euro Stoxx 50 stock market index, Orange has been the companys main brand for mobile, landline, internet and IPTV services since 2006. It originated in 1994 when Hutchison Whampoa acquired a stake in Microtel Communications during the early 1990s. It became a subsidiary of Mannesmann in 1999 and was acquired by France Télécom in 2000, the company was rebranded as Orange in July 2013. In 1792, under the French Revolution, the first communication network was developed to enable the rapid transmission of information in a warring and that was the optical telegraphy network of Claude Chappe. In 1878, after the invention of the telegraph and then the invention of the telephone. Telephone Services were added to the ministry when they were nationalised in 1889, however, it was not until 1923 that the second T appeared and the department of P&T became PTT. In 1941, a General Direction of Telecommunications was created within this ministry, then, in 1944, the National Centre of Telecommunications Studies was created to develop the telecommunications industry in France. In the 1970s, France tried extra hard to make up its delay on other countries with the programme delta LP and it was at the time when the majority of the local loop was built, that is all the cables linking the users to the operator. Moreover, with the help of French manufacturers, digital switching, the Minitel, until 1988, France Télécom was known as the Direction Générale des Télécommunications, a division of the Ministry of Posts and Telecommunications. This was in response to a European directive, aimed at making competition mandatory in public services from 1 January 1998, the 2 July 1990 Bill changed France Télécom into an operator of public law, with Marcel Roulet the first Chairman. Since then, the company has had a body corporate from the State. It was privatised by Lionel Jospins Plural Left government starting on 1 January 1998, the French government, both directly and through its holding company ERAP, continues to hold a stake of almost 27% in the company. In addition, the government Conseil of Ministers names the CEO, in 1982 Telecom introduced Minitel online ordering for its customers. In September 1995, Michel Bon was appointed to run France Télécom Group, in 1997, the capital of the new public company was successfully floated whereas the dot-com bubble phenomenon made the stock exchanges bullish. A second share offering occurred in 1998, Hutchison renamed Microtel to Orange Personal Communications Services Ltd, and on 28 April 1994 the Orange brand was launched in the UK mobile phone market
22.
Telecom Italia
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Telecom Italia is an Italian telecommunications company headquartered in Rome, which provides telephony services, mobile services, and DSL data services. The companys stock is traded in the Borsa Italiana, in 1925, the phone network was reorganised by Benito Mussolini cabinet and Stipel company was established in the same year. The original core of Telecom Italia includes also 4 more different companies, TIMO, Teti, TELVE, each of them worked in a specific geographical area. It was in 1964 that these companies merged in one single group and it was run by the Italian Ministry of Finance. SIP was a monopoly from 1964 to 1996 and Italian people had to pay the Canone Telecom in order to have a phone at home. Telecom Italia was officially created on 27 July 1994 by the merger of several telecommunication companies among which SIP, Iritel, Italcable, Telespazio and this was due to a plan of reorganization of the telecommunication sector presented by IRI to the Minister of Finance. In 1995, the mobile telephony division was spun off as TIM, interbusiness, Italy’s largest Internet network, was created and in the same period with TIN and the first ISPs, Internet became a reality in Italy too. By 2001, the company was in debt and was bought by Marco Tronchetti Provera, Telecom Italia Media, the Groups multimedia company was formed in 2003 from Seat Pagine Gialle, focussing its business on the television sector with La7 and MTV channels. After the reorganization of editorial activities, in 2005 Telecom Italia acquired Tin. it, the Telecom Italia Group also operates in South America, in Brazil as TIM Brasil, and in Argentina and Paraguay with Telecom Argentina Group. TIM Brasil has its headquarters in Rio de Janeiro. Telecom Italia had bigger debts in 2005, and, one year later, in 2007 the company was bought by Telco. Telefónica currently owns 46% of Telco, the company that controls 22% of Telecom Italia. In late 2013, Telefónica announced its intention to acquire the entirety of Telco by January 2014, in 2015, Telecom Italia Group started a rebranding process of the telephony and mobile businesses under the single TIM brand. In the same year, the Board of Directors approved the new division, the Infrastrutture Wireless Italiane, or INWIT. It was revealed in October 2015 that shareholders Vivendi would raise their stakes further in the company from its current level of 15. 49%, Telecom Italia Mobile illegally charged money for Internet providing renew subscriptions for 5 years to its customers during the free subscription renewals. On 8 August 2012, TIM Brasil became involved in a scandal in Brazilian news after the release of report by the Brazilian National Telecommunications Agency Anatel. The report points that on TIMs prepaid voice plan, called Infinity, in just one day,8.1 million calls were dropped and the total profit was approximately $2 million. It also operates in international services, for other operators and corporations
23.
GSMA
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The GSM Association is a trade body that represents the interests of mobile operators worldwide. Approximately 800 mobile operators are full GSMA members and a further 300 companies in the mobile ecosystem are associate members. The GSMA represents its members via industry programmes, working groups and it also organises the mobile industry’s largest annual exhibition and conference, the GSMA Mobile World Congress, and several other events. The GSMA is headquartered in London with regional offices in Atlanta, Hong Kong, Shanghai, Barcelona, Brussels, Brasilia, Nairobi, the Director General of the GSMA is Mats Granryd. The GSMA was formed in 1995 as the GSM MoU Association as a body to support and it traces its history back to an MoU signed in 1987 by 13 operators in 12 countries that committed to deploying GSM for mobile services. Full membership of the GSMA is open to licensed mobile operators using a GSM family technology, approximately 800 such operators around the world are full GSMA members. Associate membership of the GSMA is open to non-operator companies active in the mobile ecosystem, there are approximately 300 GSMA member companies in this category. The GSMA board has 25 representatives from the world’s largest operator groups and selected smaller operators, sunil Bharti Mittal, Founder and Chairman, Bharti Enterprises, became GSMA Chair in January 2017 and will serve a two-year term. The GSMA manages industry programmes in collaboration with its members with the aim of achieving scale and it has four active programmes, Personal Data, Connected Living, Network 2020, and Digital Commerce. It also runs industry working groups covering areas such as roaming and interconnection, fraud and security, the GSMA represents the mobile industry to governments and institutions where it advocates policy and regulatory positions on behalf of its members. As part of its Industry Purpose programme, the GSMA is supporting the United Nations’ Sustainable Development Goals, the GSMA Mobile World Congress is the largest annual exhibition and conference dedicated to the mobile industry, attracting more than 100,000 visitors in 2016. The event was first held in 1987, since 2006 the event has been hosted in Barcelona and is currently located at the Fira Gran Via and Fira Montjuïc venues. The 2016 event retained a Guinness World Record as the largest carbon neutral trade show in the world, the GSMA is the global administrator of Type Allocation Code, which is used to create the IMEI number that can uniquely identify wireless devices. It allocates official IMEI number ranges to all manufacturers of 3GPP compliant devices and records these ranges and it offers a device look up and identification service based on this database that allows authorised third-party organisations to identify the manufacturer and model of a mobile device using the IMEI
24.
Next Generation Mobile Networks
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The Next Generation Mobile Networks Alliance is a mobile telecommunications association of mobile operators, vendors, manufacturers and research institutes. It was founded by major mobile operators in 2006 as a forum to evaluate candidate technologies to develop a common view of solutions for the next evolution of wireless networks. Its objective is to ensure the successful launch of future mobile broadband networks through a roadmap for technology. Its office is in Frankfurt, Germany, the NGMN Alliance complements and supports standards organizations by providing a coherent view of what mobile operators require. The alliances project results have been acknowledged by such as the 3rd Generation Partnership Project, TeleManagement Forum. In a white paper first released in March 2006, NGMN summarized a vision for mobile broadband communications, from July 2007 to February 2008, standards and technologies were evaluated for next generation mobile networks. These were 3GPP Long Term Evolution and its System Architecture Evolution, IEEE802. 16e,802.20, the NGMN Alliance therefore approves LTE/SAE as its first compliant technology”. Also in June 2008 the alliance announced it would work with the Femto Forum to ensure femtocells benefit from the technology, as part of this work, it issued a public request for information on LTE patent pool administration. The ITU and regional bodies are developing channeling arrangements for the frequency bands identified at the ITU World Radio Conference in 2007, in September 2010, NGMN published recommendations on operational aspects of next generation networks. The document outlines requirements for self-organizing network functionalities and operations and maintenance to address these issues, in 2014, the NGMN Board decided to focus future NGMN activities on defining the end-to-end requirements for 5G. A global team has developed the NGMN 5G White Paper delivering consolidated operator requirements that support the standardisation. NGMN encourages the industry to have 5G solutions available by 2020, however, the commercial introduction of 5G is expected to vary from operator to operator. In 2015, NGMN launched a 5G-focused work-programme that will build on, furthermore, the NGMN project teams will address the areas IPR and Spectrum from a 5G perspective. Following the white paper published in March 2015, in September 2015, for example, What will 5G allow us to do compared with today. 5G will be an end-to-end system environment to enable a fully mobile and it empowers value creation enabled by sustainable business models. How will 5G enrich our everyday life according to the White Paper, in addition to supporting the evolution of the established prominent mobile broadband use cases, 5G will support countless emerging use cases with a high variety of applications. Furthermore, NGMN envisages delay-sensitive video applications, high speed entertainment applications in vehicles, there will also be new services enabled in the health and safety area with extreme requirements in terms of system reliability. In addition, future services will be delivered across a heterogeneous environment and a wide range of devices such as smartphones, wearables
25.
Terrestrial Trunked Radio
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Terrestrial Trunked Radio, a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by government agencies, emergency services, for public safety networks, rail transport staff for train radios, transport services, TETRA is a European Telecommunications Standards Institute standard, first version published 1995, it is mentioned by the European Radiocommunications Committee. TETRA uses Time Division Multiple Access with four channels on one radio carrier and 25 kHz spacing between carriers. Both point-to-point and point-to-multipoint transfer can be used, digital data transmission is also included in the standard though at a low data rate. TETRA Mobile Stations can communicate direct-mode operation or using trunked-mode operation using switching, as well as allowing direct communications in situations where network coverage is not available, DMO also includes the possibility of using a sequence of one or more TETRA terminals as relays. This functionality is called DMO gateway or DMO repeater, in emergency situations this feature allows direct communications underground or in areas of bad coverage. In addition to voice and dispatch services, the TETRA system supports several types of data communication, Status messages and short data services are provided over the systems main control channel, while packet-switched data or circuit-switched data communication uses specifically assigned channels. TETRA provides for authentication of terminals towards infrastructure and vice versa, for protection against eavesdropping, air interface encryption and end-to-end encryption is available. The common mode of operation is in a group calling mode in which a single button push will connect the user to the users in a selected call group and/or a dispatcher. It is also possible for the terminal to act as a walkie talkie. TETRA terminals can act as mobile phones, with a direct connection to other TETRA Users or the PSTN. Emergency buttons, provided on the terminals, enable the users to transmit signals, to the dispatcher. During a voice call, the communications are not interrupted when moving to another network site and this is a unique feature, which dPMR networks typically provide, that allows a number of fall-back modes such as the ability for a base station to process local calls. So called mission critical networks can be built with TETRA where all aspects are fail-safe/multiple-redundant, in the absence of a network, mobiles/portables can use direct mode whereby they share channels directly. Gateway mode - where a mobile with connection to the network can act as a relay for other nearby mobiles that are out of range of the infrastructure. TETRA also provides a point-to-point function that traditional analogue emergency services radio systems did not provide and this enables users to have a one-to-one trunked radio link between sets without the need for the direct involvement of a control room operator/dispatcher. Unlike cellular technologies, which connect one subscriber to one other subscriber, TETRA is built to do one-to-one and these operational modes are directly relevant to the public safety and professional users. Security TETRA supports terminal registration, authentication, air-interface encryption and end-to-end encryption, rapid deployment network solutions are available for disaster relief and temporary capacity provision
26.
Code-division multiple access
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Code division multiple access is a channel access method used by various radio communication technologies. CDMA is an example of access, where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies, to permit this without undue interference between the users, CDMA employs spread-spectrum technology and a special coding scheme. CDMA is used as the method in many mobile phone standards. The technology of code division multiple access channels has long been known, in the Soviet Union, the first work devoted to this subject was published in 1935 by professor Dmitriy V. Ageev. It was shown that through the use of methods, there are three types of signal separation, frequency, time and compensatory. LK-1 has a weight of 3 kg, 20–30 km operating distance, the base station, as described by the author, could serve several customers. In 1958, Kupriyanovich made the new experimental pocket model of mobile phone, to serve more customers, Kupriyanovich proposed the device, named by him as correllator. In 1958, the USSR also started the development of the Altai national civil mobile phone service for cars, the phone system weighed 11 kg. It was placed in the trunk of the vehicles of high-ranking officials, the main developers of the Altai system were VNIIS and GSPI. In 1963 this service started in Moscow and in 1970 Altai service was used in 30 USSR cities, one of the early applications for code division multiplexing is in the Global Positioning System. This predates and is distinct from its use in mobile phones, the Qualcomm standard IS-95, marketed as cdmaOne. The Qualcomm standard IS-2000, known as CDMA2000, is used by mobile phone companies. The UMTS 3G mobile phone standard, which uses W-CDMA, CDMA has been used in the OmniTRACS satellite system for transportation logistics. CDMA is a multiple access technique. A spread spectrum technique spreads the bandwidth of the data uniformly for the transmitted power. A spreading code is a code that has a narrow ambiguity function. In CDMA a locally generated code runs at a higher rate than the data to be transmitted
27.
Next-generation network
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The next-generation network is a body of key architectural changes in telecommunication core and access networks. The general idea behind the NGN is that one network transports all information and services by encapsulating these into IP packets, nGNs are commonly built around the Internet Protocol, and therefore the term all IP is also sometimes used to describe the transformation of formerly telephone-centric networks toward NGN. NGN is a different concept from Future Internet, which is focused on the evolution of Internet in terms of the variety. It offers unrestricted access by users to different service providers and it supports generalized mobility which will allow consistent and ubiquitous provision of services to users. It implies amongst others the migration of voice from an architecture to VoIP. In the cable network, NGN convergence implies migration of constant bit rate voice to CableLabs PacketCable standards that provide VoIP and SIP services. Both services ride over DOCSIS as the data layer standard. In an NGN, there is a defined separation between the transport portion of the network and the services that run on top of that transport. Increasingly applications, including voice, tend to be independent of the access network, next-generation networks are based on Internet technologies including Internet Protocol and multiprotocol label switching. At the application level, Session Initiation Protocol seems to be taking over from ITU-T H.323, initially H.323 was the most popular protocol, though its popularity decreased in the local loop due to its original poor traversal of network address translation and firewalls. For this reason as domestic VoIP services have developed, SIP has been more widely adopted. However, in voice networks where everything is under the control of the operator or telco. Nonetheless, most of the telcos are extensively researching and supporting IP Multimedia Subsystem, for voice applications one of the most important devices in NGN is a Softswitch – a programmable device that controls Voice over IP calls. It enables correct integration of different protocols within NGN, the most important function of the Softswitch is creating the interface to the existing telephone network, PSTN, through Signalling Gateways and Media Gateways. However, the Softswitch as a term may be defined differently by the different equipment manufacturers and have different functions. One may quite often find the term Gatekeeper in NGN literature and this was originally a VoIP device, which converted voice and data from their analog or digital switched-circuit form to the packet-based one. It controlled one or more gateways, as soon as this kind of device started using the Media Gateway Control Protocol, the name was changed to Media Gateway Controller. A Call Agent is a name for devices/systems controlling calls
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Wireless LAN
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This gives users the ability to move around within a local coverage area and yet still be connected to the network. A WLAN can also provide a connection to the wider Internet, most modern WLANs are based on IEEE802.11 standards and are marketed under the Wi-Fi brand name. Wireless LANs have become popular for use in the home, due to their ease of installation and they are also popular in commercial complexes that offer wireless access to their customers. Norman Abramson, a professor at the University of Hawaii, developed the worlds first wireless communication network, ALOHAnet. The system included seven computers deployed over four islands to communicate with the computer on the Oahu Island without using phone lines. Wireless LAN hardware initially cost so much that it was used as an alternative to cabled LAN in places where cabling was difficult or impossible. Early development included industry-specific solutions and proprietary protocols, but at the end of the 1990s these were replaced by standards, beginning in 1991, a European alternative known as HiperLAN/1 was pursued by the European Telecommunications Standards Institute with a first version approved in 1996. This was followed by a HiperLAN/2 functional specification with ATM influences accomplished February 2000, in 2009802. 11n was added to 802.11. It operates in both the 2.4 GHz and 5 GHz bands at a data transfer rate of 600 Mbit/s. Most newer routers are able to utilise both wireless bands, known as dualband and this allows data communications to avoid the crowded 2.4 GHz band, which is also shared with Bluetooth devices and microwave ovens. The 5 GHz band is wider than the 2.4 GHz band, with more channels. Not all channels are available in all regions, a HomeRF group formed in 1997 to promote a technology aimed for residential use, but it disbanded at the end of 2002. All components that can connect into a medium in a network are referred to as stations. All stations are equipped with wireless network interface controllers, Wireless stations fall into two categories, wireless access points, and clients. Access points, normally wireless routers, are base stations for the wireless network and they transmit and receive radio frequencies for wireless enabled devices to communicate with. The basic service set is a set of all stations that can communicate with other at PHY layer. Every BSS has an identification called the BSSID, which is the MAC address of the access point servicing the BSS, there are two types of BSS, Independent BSS, and infrastructure BSS. An independent BSS is an ad hoc network that contains no access points, an extended service set is a set of connected BSSs
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Push-to-talk
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For example, an air traffic controller usually talks on one radio frequency to all aircraft under his/her supervision. Those under the frequency can hear others transmissions while using procedure words such as over. In doing so, they are aware of others actions and intentions. Similar considerations apply to radio, the use of business band radios on construction sites. Citizens Band is another example of classic push-to-talk operation, the PTT switch is most commonly located on the radios handheld microphone, or for small hand-held radios, directly on the radio. For heavy radio users, a PTT foot switch may be used, less commonly, a separate hand-held PTT switch may be used. This type of switch was historically called a pressel, in situations where a user may be too busy to handle a talk switch, voice operated switches are sometimes employed. Some systems use PTT ID to identify the speaker, push-to-talk over cellular is a service option for a cellular phone network that enables subscribers to use their phones as walkie-talkies with unlimited range. A typical push-to-talk connection connects almost instantly, a significant advantage of PTT is the ability for a single person to reach an active talk group with a single button press, users need not make several telephone calls to coordinate with a group. Push-to-talk cellular calls similarly provide half-duplex communications — while one person transmits and this combines the operational advantages of PTT with the interference resistance and other virtues of mobile phones. Mobile push-to-talk services, offered directly some mobile carriers as well as independent companies, adds PTT functionality to smartphones, in addition to mobile handsets, some services also work on a laptop, desktop, and tablet computers. Recent development in PTT communications is the appearance of apps on smartphones, wireless carrier-grade PTT systems have adapted to and adopted the smartphone platform by providing downloadable apps that support their PTT systems across many mobile platforms. Over-the-top applications are not dependent on a carrier and nearly as fast as carrier implementations. Talk-IP, Twisted Pair, Wave, Zello, Talko, Orion Labs, and Voxer may offer similar services to carriers.0 –26 February 2008
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Subscriber identity module
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It is also possible to store contact information on many SIM cards. SIM cards are used on GSM phones, for CDMA phones. SIM cards can also be used in satellite phones, the SIM circuit is part of the function of a Universal Integrated Circuit Card physical smart card, which is usually made of PVC with embedded contacts and semiconductors. SIM cards are transferable between different mobile devices, the SIM was initially specified by the European Telecommunications Standards Institute in the specification with the number TS11.11. This specification describes the physical and logical behaviour of the SIM, with the development of UMTS the specification work was partially transferred to 3GPP. 3GPP is now responsible for the development of applications like SIM and USIM. The first SIM card was developed in 1991 by Munich smart-card maker Giesecke & Devrient, many non-contractual pay-as-you-go arrangements require you to actively use credit at least once every three months lest your account expires. This is sometimes associated with the SIM card being made inactive by the network, there are three operating voltages for SIM cards,5 V,3 V and 1.8 V. The operating voltage of the majority of SIM cards launched before 1998 was 5 V. SIM cards produced subsequently are compatible with 3 V and 5 V, modern cards support 5 V,3 V and 1.8 V. Modern SIM cards allow applications to be loaded when the SIM is in use by the subscriber and these applications communicate with the handset or a server using SIM application toolkit, which was initially specified by 3GPP in TS11.14. ETSI and 3GPP maintain the SIM specifications, the specifications are, ETSI TS102223, ETSI TS102241, ETSI TS102588. SIM toolkit applications were written in native code using proprietary APIs. In order to allow interoperability of the applications, Java Card was taken as the solution of choice by ETSI, additional standards and specifications of interest are maintained by GlobalPlatform. SIM cards store network-specific information used to authenticate and identify subscribers on the network, the most important of these are the ICCID, IMSI, Authentication Key, Local Area Identity and Operator-Specific Emergency Number. The SIM also stores other carrier-specific data such as the SMSC number, Service Provider Name, Service Dialing Numbers, Advice-Of-Charge parameters, SIM cards can come in various data capacities, from 8 KB to at least 256 KB. All allow a maximum of 250 contacts to be stored on the SIM, but while the 32 KB has room for 33 Mobile Network Codes or network identifiers, the 64 KB version has room for 80 MNCs. This is used by operators to store information on preferred networks. Each SIM is internationally identified by its integrated circuit card identifier, ICCIDs are stored in the SIM cards and are also engraved or printed on the SIM card body during a process called personalisation
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Near-field communication
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NFC devices are used in contactless payment systems, similar to those used in credit cards and electronic ticket smartcards and allow mobile payment to replace/supplement these systems. NFC is used for networking, for sharing contacts, photos, videos or files. NFC-enabled devices can act as electronic identity documents and keycards, NFC offers a low-speed connection with simple setup that can be used to bootstrap more capable wireless connections. Similar ideas in advertising and industrial applications were not generally successful commercially, outpaced by technologies such as barcodes, NFC protocols established a generally supported standard. When one of the devices has Internet connectivity, the other can exchange data with online services. NFC-enabled portable devices can be provided with software, for example to read electronic tags or make payments when connected to an NFC-compliant apparatus. NFC reader/writer—enables NFC-enabled devices to read information stored on inexpensive NFC tags embedded in labels or smart posters, NFC peer-to-peer—enables two NFC-enabled devices to communicate with each other to exchange information in an adhoc fashion. NFC tags are passive data stores which can be read, and under some circumstances written to and they typically contain data and are read-only in normal use, but may be rewritable. Applications include secure personal data storage, NFC tags can be custom-encoded by their manufacturers or use the industry specifications. The standards were provided by the NFC Forum, the forum was responsible for promoting the technology and setting standards and certifies device compliance. Secure communications are available by applying encryption algorithms as is done for credit cards, NFC standards cover communications protocols and data exchange formats and are based on existing radio-frequency identification standards including ISO/IEC14443 and FeliCa. The standards include ISO/IEC18092 and those defined by the NFC Forum, in addition to the NFC Forum, the GSMA group defined a platform for the deployment of GSMA NFC Standards within mobile handsets. GSMAs efforts include Trusted Services Manager, Single Wire Protocol, testing/certification, a patent licensing program for NFC is under deployment by France Brevets, a patent fund created in 2011. This program was under development by Via Licensing Corporation, an independent subsidiary of Dolby Laboratories, a platform-independent free and open source NFC library, libnfc, is available under the GNU Lesser General Public License. Present and anticipated applications include contactless transactions, data exchange and simplified setup of more complex such as Wi-Fi. This is used for identification, authentication and tracking,1983 The first patent to be associated with the abbreviation RFID was granted to Charles Walton. 1997 Early form patented and first used in Star Wars character toys for Hasbro, the patent was originally held by Andrew White and Marc Borrett at Innovision Research and Technology. The device allowed data communication between two units in close proximity,2002 Sony and Philips agreed to establish a technology specification and created a technical outline on March 25,2002
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Mobile payment
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Mobile payment generally refer to payment services operated under financial regulation and performed from or via a mobile device. Instead of paying cash, cheque, or credit cards. Although the concept of using non-coin-based currency systems has a long history, Mobile payment is being adopted all over the world in different ways. In 2008, the market for all types of mobile payments was projected to reach more than $600B globally by 2013. The mobile payment market for goods and services, excluding contactless payments using near field communication, investment on mobile money services is expected to grow by 22. 2% during the next two years across the globe. It will result in revenue share of mobile money reaching up to 9% by 2018, asia and Africa will observe significant growth for mobile money with technological innovation and focus on interoperability emerging as prominent trends by 2018. These payment networks are used for micropayments. Mobile payments are becoming a key instrument for PSPs and other participants, in order to achieve new growth opportunities. The EPC states that “new technology solutions provide an improvement to the operations efficiency, ultimately resulting in cost savings. Online companies like PayPal, Amazon Payments, and Google Wallet also have mobile options and these systems can be integrated with directly or can be combined with operator and credit card payments through a unified mobile web payment platform. A simple mobile web payment system can include a credit card payment flow allowing a consumer to enter their card details to make purchases. This process is familiar but any entry of details on a phone is known to reduce the success rate of payments. The consumer uses the mobile billing option during checkout at an e-commerce site—such as an online gaming site—to make a payment, after two-factor authentication involving a PIN and One-Time-Password, the consumers mobile account is charged for the purchase. Convenience – No pre-registration and no new software is required. Easy – Its just another option during the checkout process, fast – Most transactions are completed in less than 10 seconds. The merchant involved is informed of the payment success and can release the paid for goods. A Multimedia Messaging Service can also deliver barcodes which can then be scanned for confirmation of payment by a merchant and this is used as an electronic ticket for access to cinemas and events or to collect hard goods. Inhibiting factors of Premium SMS include, Poor reliability – transactional premium SMS payments can easily fail as messages get lost, slow speed – sending messages can be slow and it can take hours for a merchant to get receipt of payment
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Orthogonal frequency-division multiple access
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Orthogonal frequency-division multiple access is a multi-user version of the popular orthogonal frequency-division multiplexing digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users and this allows simultaneous low-data-rate transmission from several users. The advantages and disadvantages summarized below are further discussed in the Characteristics, see also the list of OFDM key features. Allows simultaneous low-data-rate transmission from several users, lower maximal transmission power for low-data-rate users. Further improves OFDM robustness to fading and interference, flexibility of deployment across various frequency bands with little needed modification to the air interface. Averaging interferences from neighboring cells, by using different basic carrier permutations between users in different cells, interferences within the cell are averaged by using allocation with cyclic permutations. Enables single-frequency network coverage, where coverage problem exists and gives excellent coverage, offers frequency diversity by spreading the carriers all over the used spectrum. Higher sensitivity to frequency offsets and phase noise, asynchronous data communication services such as web access are characterised by short communication bursts at high data rate. Few users in a base station cell are transferring data simultaneously at low constant data rate, the OFDM diversity gain and resistance to frequency-selective fading may partly be lost if very few sub-carriers are assigned to each user, and if the same carrier is used in every OFDM symbol. Adaptive sub-carrier assignment based on fast feedback information about the channel, dealing with co-channel interference from nearby cells is more complex in OFDM than in CDMA. It would require dynamic channel allocation with advanced coordination among adjacent base stations, the fast channel feedback information and adaptive sub-carrier assignment is more complex than CDMA fast power control. Based on feedback information about the conditions, adaptive user-to-subcarrier assignment can be achieved. OFDMA can be seen as an alternative to combining OFDM with time-division multiple access or time-domain statistical multiplexing communication, low-data-rate users can send continuously with low transmission power instead of using a pulsed high-power carrier. Constant delay, and shorter delay, can be achieved, in spectrum sensing cognitive radio, OFDMA is a possible approach to filling free radio frequency bands adaptively. Timo A. Weiss and Friedrich K. Jondral of the University of Karlsruhe proposed a pooling system in which free bands sensed by nodes were immediately filled by OFDMA subbands. The radio interface was formerly named High Speed OFDM Packet Access, the Qualcomm Flarion Technologies Mobile Flash-OFDM the now defunct Qualcomm/3GPP2 Ultra Mobile Broadband project, intended as a successor of CDMA2000, but replaced by LTE. OFDMA is also an access method for the IEEE802.22 Wireless Regional Area Networks. The project aims at designing the first cognitive radio based standard operating in the VHF-low UHF spectrum, the term OFDMA is claimed to be a registered trademark by Runcom Technologies Ltd. with various other claimants to the underlying technologies through patents
