Signaling System No.7 Protocol Architecture And Sevices part 6 docx

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Signaling System No.7 Protocol Architecture And Sevices part 6 docx

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Regional Standards N orth America, Europe, and Japan play a major role in the ITU-T and also set their own regional standards based on the ITU-T recommendations. E TSI ETSI is a nonprofit organization responsible for setting standards for telecommunications systems in Europe. ETSI was set up by the CEC (Commission of the European Communities). ETSI is an open forum that unites 728 members from 51 countries, representing administrations, network operators, manufacturers, service providers, and users. Any European organization proving an interest in p romoting European telecommunications standards has the right to represent that interest in ETSI and, thus, to directly influence the standards-making process. The purpose of ETSI was to create something in between the international level and the national level for pan-European use so that EU member countries could have cross-border signaling that was not as restricted as that found on the international level. 3rd Generation Partnership Project When the ITU solicited solutions to meet the requirements laid down for IMT- 2000 (3G cellular), various standards groups proposed varying technologies. ETSI p roposed a Wideband Code Division Multiple Access (WCDMA) solution using FDD. Japan proposed a WCDMA solution using both TDD and FDD. The Koreans p roposed two types of CDMA solutions—one similar to the ETSI solution and one more in line with the North American solution (CDMA 2000). Instead of having different regions working alone, it was decided that it would be better to pool resources. To this end, the 3rd Generation Partnership Project (3GPP) was created to work on WCDMA, and 3GPP2 was formed to work on CDMA-2000. 3GPP is a collaboration agreement that was established in December 1998. It brings together a number of telecommunications standards bodies called organization partners. The current organization partners are Association of Radio Industries and Businesses (ARIB—Japan), China Wireless Telecommunication Standards group (CWTS—China), European Telecommunications Standards Institute (ETSI—Europe), Committee T1 (North America), Telecommunications Technology Association (TTA—Korea), and Telecommunication Technology Committee (TTC—Japan). The Telecommunications Industry Association (TIA— N orth America) is an observer to 3GPP. The scope of 3GPP was subsequently amended to include the maintenance and development of the Global System for Mobile communication (GSM), General Packet Radio Service (GPRS), and Enhanced Data rates for GSM Evolution (EDGE). Previously, it focused only on developing standards for third-generation mobile systems. The GSM standard has been transferred to 3GPP from ETSI, although the vast majority of individual member organizations in 3GPP come from the ETSI membership list. 3GPP's third-generation systems operate in at least the five regions of the partner standards bodies—this is a big improvement over the GSM situation, which is incompatible with the Japanese second-generation system and, in terms of frequency band employed, even the GSM implementations in the U.S. The advantages of this multiregional approach are no doubt why 3GPP was formed. 3rd Generation Partnership Project 2 3GPP2 is to CDMA-2000 what 3GPP is to W-CDMA. Furthermore, 3GPP2 was created in the image of 3GPP. They develop 3G standards for carriers that currently have CDMA systems (such as IS-95 or TIA/EIA-95) installed. This group works closely with TIA/EIA TR-45.5, which originally was responsible for CDMA standards, as well as other TR-45 subcommittees—TR-45.2 (network), TR-45.4 ("A" interface), and TR-45.6 (packet data). ETSI is not involved in any way with 3GPP2, and it does not publish the output of 3GPP2. Although 3GPP and 3GPP2 are separate organizations, they cooperate when it comes to specifying services that ideally should be the same (from the users' perspective), regardless of infrastructure and access technology. It should also be noted that quite a few equipment manufacturers need to keep their fingers in all pies and consequently are members of both projects. The five officially recognized standards-developing organizations that form the 3GPP2 collaborative effort (organization partners) are ARIB, CWTS, TIA/EIA, TTA, and TTC. In addition, market representation partners are organizations that can offer market advice to 3GPP2. They bring to 3GPP2 a consensus view of market requirements (for example, services, features, and functionality) falling within the 3GPP2 scope. These organizations are the CDMA develop group (CDG), the Mobile Wireless Internet Forum (MWIF), and the IPv6 forum. 3GPP2 is the culmination of efforts led by ANSI, TIA/EIA, and TIA/EIA TR-45. TIA/EIA has been chosen to be secretariat to 3GPP2. Observers from ETSI, Telecommunications Standards Advisory Council of Canada (TSACC), and China p articipate in 3GPP2. < Day Day Up > < Day Day Up > National and Industry Standards N ational standards are based on either ITU-T standards for nationalization or regional standards that are ITU-T standards that have been regionalized in much the same way that national standards are produced. A NSI ANSI was founded in 1918 by five engineering societies and three government agencies. The Institute remains a private, nonprofit membership organization supported by a diverse constituency of private-sector and public organizations. ANSI's T1 committee is involved in the standardization of SS7. These standards are developed in close coordination with the ITU-T. ANSI is responsible for accrediting other North American standards organizations, including the Alliance for Telecommunications Industry Solutions (ATIS), EIA, and TIA. ANSI has more than 1000 company, organization, government agency, institutional, and international members. ANSI defines protocol standards at the national level. It works by accrediting qualified organizations to develop standards in the technical area in which they have expertise. ANSI's role is to administer the voluntary consensus standards system. It provides a neutral forum to develop p olicies on standards issues and to serve as an oversight body to the standards development and conformity assessment programs and processes. T1 Committee The T1 Committee is sponsored by ATIS. It is accredited by ANSI to create network interconnections and interoperability standards for the U.S. Telcordia (Formerly Bellcore) Before its divestiture in 1984, the Bell System was a dominant telecom service p rovider and equipment manufacturer. It provided most of the service across the U.S. and set the de facto standards for the North American telecommunications network. Bell Communications Research (Bellcore) was formed at divestiture in 1984 to p rovide centralized services to the seven regional Bell holding companies and their operating company subsidiaries, known as Regional Bell Operating Companies (RBOCs). Bellcore was the research and development arm of the former Bell System (the "baby Bells") operating companies. It defined requirements for these companies. These were documented in its Technical Advisories (TA series), Technical References (TR series), and Generic Requirements (GR series). Although Bellcore specifications are somewhat prevalent in the telecommunications industry, they are not prescribed standards, although they had often become the de facto standards. This is because they were originally created in a closed-forum fashion for use by the RBOCs. Even post-divestiture, the specifications remain focused on the interests of the RBOCs. As such, they are industry standards but are not national standards. Bellcore was acquired by Science Applications International Corporation (SAIC) in 1997 and was renamed Telcordia Technologies in 1999. Although Telcordia was p reviously funded by the RBOCs, it now operates as a regular business, providing consulting and other services. The Telcordia specifications are derived from the ANSI specifications, but it should be noted that Telcordia has often been a driver for the ANSI standards body. The core ANSI standards [1 -4] and the Bellcore standards [113] for SS7 are nearly identical. However, Bellcore has added a number of SS7 specifications beyond the core GR-246 specifications for RBOCs and Bellcore clients. TIA/EIA TIA is a nonprofit organization. It is a U.S. national trade organization with a membership of 1000 large and small companies that manufacture or supply the p roducts and services used in global communications. All forms of membership within the organization, including participation on engineering committees, require corporate membership. Engineering committee participation is open to nonmembers also. Dues are based on company revenue. TIA represents the communications sector of EIA. TIA/EIA's focus is the formation of new public land mobile network (PLMN) standards. It is an ANSI- accredited standards-making body and has created most of the PLMN standards used in the U.S. One very well-known standard is IS-41, which is used as the Mobile Application Part (MAP) in CDMA networks in the U.S. to enable cellular roaming, authentication, and so on. IS-41 is described in Chapter 13 , "GSM MAP and ANSI-41 MAP." TIA/EIA develops ISs. Following the publication of an IS, one of three actions must be taken—reaffirmation, revision, or rescission. Reaffirmation is simply a review that concludes that the standard is still valid and does not require changes. Revision is exactly that—incorporating additional material and/or changes to technical meaning. Rescission is the result of a review that concludes that the standard is no longer of any value. If the majority of ANSI members agree on the TIA/EIA interim standard, it becomes a full ANSI national standard. It is for this reason that IS-41 is now called ANSI-41. IS-41 was revised a number of times and then became a national standard. It progressed to Revision 0, then Revision A, then Revision B, then Revision C, and then it became a nationalized standard—ANSI-41 on Revision D. Currently it is on Revision E, and Revision F is planned. In addition to ISs, TIA/EIA also publishes Telecommunications Systems Bulletins (TSBs). These provide information on existing standards and other information of importance to the industry. TIA/EIA is composed of a number of committees that develop telecommunications standards. The TR committees are concerned with PLMN standards. Nine TR committees currently exist, as shown in Table 2-2 . Table 2-2. TIA/EIA TR Committees TIA/EIA TR Committee Number TIA/EIA TR Committee Name TR-8 Mobile and Personal/Private Radio Standards TR-14 Point-to-Point Communications TR-29 Facsimile Systems and Point-to-Multipoint TR-30 Data Transmission Systems and Equipment TR-32 Personal Communications Equipment TR-34 Satellite Equipment and Systems TR-41 User Premises Telecommunications Requirements TR-45 Mobile and Personal Communications Systems Standards TR-46 Mobile & Personal Communications 1800 Standards A TIS ATIS is the major U.S. telecom standards organization besides TIA/EIA. Most notably, it is responsible for ANSI SS7 standards. This organization was p reviously called Exchange Carriers Standards Association (ECSA). B SI The BSI was formed in 1901 and was incorporated under the Royal Charter in 1929. BSI is the oldest national standards-making body in the world. Independent of government, industry, and trade associations, BSI is an impartial body serving both the private and public sectors. It works with manufacturing and service industries, businesses, and governments to facilitate the production of British, European, and international standards. As well as facilitating the writing of British standards, it represents UK interests across the full scope of European and international standards committees. N IC C The Network Interoperability Consultative Committee (NICC) is a UK telecommunications industry committee that acts as an industry consensus group in which specifications and technical issues associated with network competition can be discussed. It also is a source of advice to the Director General of Telecommunications for the Office of Telecommunications (OFTEL) on the harmonization of interconnection arrangements. N ICC deals with particular issues via its interest groups, which aim t o represent p articular sectors of the industry. They include representatives of network operators, public exchange manufacturers, terminal equipment suppliers, and service providers. There is also a separate users' panel that works electronically to p rovi d e a user's perspective on NICC activities. At the NICC's top level is the NICC Board, which is composed mainly of representatives of the interest groups that form the whole NICC. PNO is the Public N etwork Operators interest group. Company representatives can join the appropriate interest groups directly, but the board members are elected from the interest group participants. Technical issues addressed so far by the NICC include the further development of interconnect signaling standards, methods of achieving geographic and nongeographic number portability, and defining interfaces for service providers. N ICC has defined UK C7 (IUP) [40] signaling independent of British Telecom N etwork Requirements (BTNR) and has developed intelligent network and database solutions for number portability. I ETF The Internet Engineering Task Force (IETF) is a nonprofit organization that is composed of a vast number of volunteers who cooperate to develop Internet standards. These volunteers come from equipment manufacturers, research institutions, and network operators. The process of developing an Internet standard is documented in RFC 2026. A brief overview is provided here. An Internet standard begins life as an Internet Draft (ID), which is just an early specification. The draft can be revised, replaced, or made obsolete at any time. The draft is placed in the IETF's IDs directory, where anyone can view it. If the draft is not revised within 6 months or has not been recommended for publication as an RFC, it is removed from the directory and ceases to exist. If the Internet Draft is sufficiently complete, it is published as an RFC and is given an RFC number. However, this does not mean that it is already a standard. Before a RFC becomes a proposed standard, it must have generated significant interest in the Internet community and must be stable and complete. The RFC does not have to be implemented before becoming a proposed standard. The next step is that the RFC changes status from a proposal to a draft standard. For this to happen, there must have been at least two successful implementations o f the specification, and interoperability must have been demonstrated. The final step to turn the RFC into a standard is to satisfy the Internet Engineering Steering Group (IESG). The IESG needs to be satisfied that the specification is both stable and mature and that it can be successfully deployed on a large scale. When the RFC becomes a standard, it is given a standard (STD) number, but it retains its previous RFC number. STD 1 lists the various RFCs and is updated p eriodically. One working group within the IETF that is of particular interest in relation to SS7 is Sigtran. Sigtran is concerned with the transport of signaling within IP-based networks including ISDN, SS7/C7, and V5. It is described in Chapter 14 , "SS7 in the Converged World." The Sigtran architecture is defined in RFC 2719, Framework Architecture for Signalling Transport. Other RFCs and IDs relate to Sigtran. See Appendix J , "ITU and ANSI Protocol Comparison."  . consensus standards system. It provides a neutral forum to develop p olicies on standards issues and to serve as an oversight body to the standards development and conformity assessment programs and. Equipment and Systems TR-41 User Premises Telecommunications Requirements TR-45 Mobile and Personal Communications Systems Standards TR- 46 Mobile & Personal Communications 1800 Standards. interconnect signaling standards, methods of achieving geographic and nongeographic number portability, and defining interfaces for service providers. N ICC has defined UK C7 (IUP) [40] signaling

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