British Telecommunications Plc says that its pilot Integrated Services Digital Network, IDA it stands for Integrated Digital Access will be upgraded to CCITT ISDN basic service compatibility by March 1988. By that time the company will have an I420 customer interface to X21. Telecom had originally hoped to be compatible with the basic 2B+1D system, which refers to a combination of two 64Kbps voice and data B channels and one 16Kbps signalling channel, by the end of 1987. Telecom has also signed a quadrapartite agreement with the public telecommunications authorities of France, Germany and Italy to head together into international ISDN. The quartet will work together to produce primary rate 30B + 1D ISDN services that can be transferred across each other’s borders. The French PTT, the Direction Ge’ne’rale de Te’le’communications, announced that it was the first European country to have a commercial CCITT-compatible basic access service in place in September, and the Bundespost has begun ISDN trials in Germany. Telecom’s IDA is currently made up of one 64Kbps channel for voice and data and one 8Kbps signalling channel.