56K Modem Standard Continues to Break New Ground

Geneva, October 27, 1998 — At the recently held meeting of Study Group 16, the multimedia group of the Telecommunications Standardization Sector of the International Telecommunication Union, approval of the new V.90 (56 K) modem standard was completed with the unanimous agreement of the Study Group. At the same meeting, the approval process was initiated for a new all-digital version of the same technology which is to be known as V.91.

The ITU, a specialized agency of the United Nations, coordinates global communications standards. Study Group 16 of the ITU Telecommunication Standardization Sector (ITU-T) where the work on modem standards is carried out, is responsible for the development of standards for multimedia systems.

The new V.90 Recommendation, is already finding wide deployment for Internet and on-line service access. V.90 modems are designed for use on normal telephone lines where the connections are analogue at the customers premises and digital at the service providers premises. Unlike other modem standards, V.90 modems take advantage of the characteristics of the digital to analogue converters present in the telephone network to achieve hitherto unobtainable high rates of transmission. Download speeds of up to 56,000 bits per second (bit/s) are possible, depending on telephone line conditions, with upload speeds of up to 33,600 bit/s.

Manufacturers formerly producing modems based on proprietary schemes have already largely migrated to the new standard. It is estimated that over 20 million V.90 modems have been supplied since the standard was "determined" for approval in February this year. According to industry analysts, the V.90 Recommendation is expected to boost modem sales significantly. Point-Topic, a market researcher, estimates the revenue from 56kbit/s modems will rise to $4.3 billion in the year 2000 from $600 million in 1997.

Work began on the development of V.90 (previously referred to as V.pcm) in the ITU-T in March 1997 and, following agreement on all substantive technical issues, the first stage of approval took place in February of this year. With final approval now granted the new Recommendation has been completed in record time.

The V.91, all-digital extension to V.90, allows modem signals to be transmitted through all-digital telephone connections which are configured for speech rather than data signals. Such connections, which terminate digitally at both the customer's and service provider's premises, have hitherto only been able to achieve data rates of 33,600 bit/s, however the use of V.91 modems will allow data to be transmitted on these lines at close to 64,000 bit/s. The standard is expected to be particularly useful on ISDN connections where a data bearer channel is not available or cannot be guaranteed.