Integration of Universal Mobile Telecommunication Systems in future B-ISDN environment

European R&D initiatives concerning mobile systems have lead to the definition of Universal Mobile Telecommunication Systems (UMTS). In particular while spectrum allocation bandwidth and access technique have been defined, the radio interface is currently under standardisation. If ATM will represent the winning technology, integration between PSTN and ATM based networks will be realised. Independently of the chosen transport technology, a unique upper-layer protocol-IP or standardised signalling protocols-should be provided. This paper is aimed at proposing an extension of the signalling protocols standardised for ATM fixed networks by ITU-T, to support mobile issues and achieve a B-ISDN integrated environment.