Telecommunications is a major industry sector for two main reasons: First, it generates vast amounts of revenue every year, and second, it touches every aspect of life and business. Networking is an international phenomenon, and recommendations have to be made on how systems and networks should interoperate. Standardization within the industry is intended to perform three basic functions:
Facilitate interconnection between different users.
Facilitate the portability of equipment within different regions and applications, with the intent of increasing market size, resulting in reduced costs for all.
Ensure equipment interoperability, so that different vendors' products work with each other.
Standards bodies that make such recommendations have traditionally been active in Europe, North America, and Japan. In recent years, the Internet Society (ISOC) has also become an increasingly important organization.
The ITU is a body of the United Nations that includes members from around the world. Three specific groups within the ITU are relevant to telecommunications. The ITU-T, the telecommunications standardization sector, develops recommendations for wireline networks. ITU-R, the radio communications standardization sector, deals with the wireless arena. The ITU-D sector works on standards for developing nations. The ITU standards are followed throughout most of the world, including Africa, most of Asia-Pacific, Europe, Latin America, and the Middle East.
Standards Organization Time LineThe following time line shows some of the important dates in the history of standards organizations:
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The second major standards body is the America National Standards Institute (ANSI), whose recommendations are followed throughout North America, as well as in some Asian countries.
The third major body is the Telecommunications Technology Committee, which is followed in Japan.
ISOC has an agreement to work with the ITU to ensure that developments do not take place separately in evolving the PSTN versus the Internet. These organizations are working toward converging networks on the same sets of requirements and functions.
In order to make room for the many often conflicting interests, the international standards-making organizations concentrate on producing what are known as base standards. These base standards contain allowable variants or options, which are defined by the implementer. By adopting any of the variants, or options, the implementer is compliant with the standard, but there is no guarantee that the equipment will interoperate with the equipment of other vendors. This problem of interoperability and internetworking is addressed by regional and national standards bodies, often involving trade organizations and users groups. These groups adapt the international base standards as functional standards, which contain a limited amount of agreed-upon allowable options. These groups also develop test specifications and methods, and independent test houses then perform the necessary conformance testing and certify products that meet the requirements. (See Figures 2.20 and 2.21.)
Table 2.2 lists some of the key standards organizations throughout the world.
Table 2.2. Standards Organizations | |
Region | Standards Organizations |
International | ITU, ITU-T, ITU-R, ITU-D, IEC, ISO |
Australia | ACA, ACC, AIIA, ATUG |
Europe | AFNOR (France), CEN and CENLEC, CEPT, DIN (Germany), DTI (UK), ETSI, European Community (EU) |
Japanese | JISC, TTC |
New Zealand | ITANZ |
North America | ANSI (USA), EIA, FCC (USA), IEEE, NIST, SCC (Canadian) |
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