The ITU Telecommunication Standardization Sector (ITU-T) fulfills a vital function – overseeing the development of harmonized technical standards that make it possible for equipment developed by vendors around the world to seamlessly inter-operate, allowing users to communicate transparently across a vast range of different, interconnected networks.

ITU Recommendations are developed through the voluntary, co-operative efforts of hundreds of public and private sector representatives, who participate in the Telecommunication Standardization Sector's 14 technical Study Groups. Comprised of experts from telecommunications operators, manufacturers, software developers, regulatory authorities and government, these groups work to define new technologies and refine existing standards to ensure the world's telecommunications networks keep pace with today's rapid technical evolution.

In recognition of the need for faster, more responsive standards development, ITU-T continued its efforts to streamline the working methods of the Sector and increase cooperation with other Standards Developing Organizations (SDOs), making provisions for the referencing of SDO texts in ITU-T Recommendations to avoid unnecessary duplication of work.

ITU-T's commitment to reducing the development time for standards has resulted in a reduction of 80% in the time-to-market of Recommendations over the last 10 years, with the average development cycle now down to just nine months.

Standardization Landmarks

Throughout the course of every year, hundreds of experts meet at ITU headquarters and elsewhere, freely contributing their time and expertise to developing the global standards which lie at the heart of today's increasingly complex communications networks.

ITU-T formally adopted 362 new or revised Recommendations during 1999 – well over one new or updated standard for every working day. Among the most important of these were new standards for IP-based voice and data transmission, optical networking, high-speed modems and IMT-2000 third generation mobile networks.

To meet the growing demands of high-bandwidth applications development, ITU-T enhanced its work in the area of broadband and multimedia networks. At a meeting in Santiago de Chile, in May, Sector members finalized details of the new Gateway Control Protocol standard for gateway devices capable of exchanging voice, video, fax and data between circuit-switched and packet-switched networks. With formal approval expected in the year 2000, this new standard will form an important extension of ITU's existing H.323 family of Recommendations, which cover multimedia transmission over IP networks.

Important progress was made on the G.990 series of Recommendations covering Digital Subscriber Line (DSL) transceivers supporting high bandwidth Internet-based services. At the same time, a new series of Recommendations – the Y series – was established to cover the Global Information Infrastructure (Recommendations up to Y.800) and Internet Protocol aspects of telecommunication networks (the Y.1000 series). Several Recommendations have already been drafted in the Y.1000 series by a range of ITU-T Study Groups as part of the IP Project, a Sector initiative aimed at facilitating the interconnection of IP-based networks with the existing public switched telephone network (PSTN).

In the area of high-speed data exchange, work continued apace on the V.90 series of Recommendations, with standards for the V.90 and V.91 modems approved. Work on the V.92 modem standard also progressed quickly, with a finalized version expected in the year 2000.

As regards IMT-2000, the Telecommunication Standardization Sector approved important Recommendations in the Q.1700 series, covering the interfaces which will form the basis of tomorrow's third generation mobile networks and specifications for network interconnection and global roaming. Recommendations defining enhanced management and security for IMT-2000 systems will be a major priority in the year 2000.

High-Speed Building Blocks

The Sector made significant progress in developing standards for the advanced technologies which will form the building blocks of tomorrow's high-speed networks, such as ATM, ADSL, SDH, optical switching and wave division multiplexing (WDM). In line with efforts to speed development of technologies which will support future broadband applications, a new area of study devoted to optical networking was also created.

To further deployment of ADSL technology, which is already beginning to serve as an important conduit for broadband services, ITU-T approved a new set of global standards aimed at harmonizing ADSL transmission around the world. The standards, which include G.992.1, covering ADSL transmission at rates up to 7Mbps and G.992.2, supporting transmission at up to 1.5Mbps, will enhance the interoperability of new ADSL equipment and provide a technically stable base for future development.

In addition, draft new and revised Recommendations were developed in areas including Full Mode Internet facsimile, call establishment procedures for fax over IP networks, higher resolution for Group 4 fax systems, and transmission of voice data files.

The Sector also worked cooperatively with other regional Standards Developing Organizations, including ISO, IEC and IETF and other forums and consortia, to develop new Recommendations relating to numbering, addressing and security for IP networks.

Convergence

With convergence continuing to blur the distinction between different kinds of equipment, ITU-T also developed key standards for systems from digital television and audio broadcasting to cable TV and digital image formats. New Recommendations covering cable networks included J.117 Home Digital Network Interface Specification, which provides the means for linking cable feeds with videocassette recorders and digital television sets. Extensions of this important standard will soon apply to personal computers and other networked home devices.

The Sector also continues to work to develop new Recommendations covering distribution of broadcast programmes over IP networks, the use of IP-based cable networks for supplementary advanced services, and quality and security of MPEG-2 digital television bitstreams.

Numbering and Tariffing

As the body charged with responsibility for the management of global numbering, ITU continued its efforts to optimize the use of increasingly scarce numbering resources such as international access codes. The Sector, through the Telecommunication Standardization Bureau (TSB), also assigned an additional 3,100 Universal International Freephone Numbers. Some 18,485 UIFN numbers had been assigned by the end of 1999, with around 260 new requests received each month.

In the complex area of tariffing, seven Recommendations on tariff principles were drafted, and the Sector approved three new remuneration frameworks which will constitute an important element in the reform of the international accounting rate system. The Group also considered guidelines for bilateral negotiation of transitional arrangements towards cost-oriented pricing, and approved tariff principles for new services using Global Mobile Personal Communications by Satellite (GMPCS) and ATM technology.

Y2K Task Force

ITU-T devoted considerable resources to ensuring that the world's telecommunications networks effected a smooth, fault-free transition to the next millennium. A special Y2K Task Force monitored responses to a millennium compliance questionnaire from more than 500 operators in 174 countries and territories, and facilitated inter-carrier testing on international routes, mobile voice services, telex, data networks, and high-end systems including Intelligent Networks, Operator and Supplementary Services.

Co-operation with Other SDOs