Monday, April 7, 2003		Feature

INTERNET has changed the way we deliver and receive information and the way we use it for business, entertainment, planning and living.

But today, the Internet access at homes and offices is based on the telephone network. The Internet access today appears to be simple: just take a telephone line, connect a modem and a computer and dial an Internet Service Provider (ISP). A dial-up connection to an ISP router gives a user access to everyone and everything on Internet. The telephone network is designed to handle 0.1Erlang traffic per subscriber. This is generally adequate for telephony. However, Internet sessions are usually of long duration, very often even exceeding an hour. As a significant percentage of telephone users start using Internet, the load on the telecom network would far exceed 0.1E per subscriber, resulting into severe congestion and eventual collapse. If this has not happened so far, it is only because a small percentage of telephone users have started using Internet. The second problem is associated with the local call charges associated with using Internet in this manner. The telephone call for Internet costs Rs.26 per hour in Indian cities today, in addition to the charges payable to ISPs.

Thirdly, the analog modem-to-modem link between the subscriber and the ISP is unreliable and the connection often drops.

Internet communication is not continuos but bursty. Packets are transmitted to and from Internet in bursts, with the communication almost silent most of the time. A circuit switched connection on telephone network, however, is unable to take advantage of this and occupies resources throughout the connection, and thereby congesting the network.

This Internet tangle requires a different approach in order to support future growth. An ideal solution is to develop an Access Network technology that separates the Internet data from the voice and not allowing it to interfere with the telephone network. By keeping all these factors in mind a team of Indian scientists invented a new technology known as CorDECT.(Cordless Digital Enhanced Cordless Telecommunications). CorDECT technology has been jointly developed by the Indian Institute of Technology (IIT), Chennai, and Midas Technologies with a joint research effort by US engineers. The main system developers are Padamshree Prof. Ashok Jhunghunwale and Prof. Bhaskar Ramamurthi (both from IIT, Chennai). CorDECT system demultiplexs voice from data at the interface unit or at Access Centre (AC), which solves the Internet problem as the Internet traffic does not enter the telephone network at all. By splitting data and voice, data can be handled directly by the ISP and voice by PSTN.