Integration Of UMTS And B-ISDN: Is It Possible Or Desirable? In the future, existing fixed networks will be complemented by mobile networks with similar numbers of users. These mobile users will have identical requirements and expectations to the fixed users, for on-demand applications of telecommunications requiring high bit-rate channels. It will be necessary for these fixed and mobile networks to interoperate in order to pass data, in real time and at high speeds, between their users. But how far must this interoperation be taken? How much integration of the fixed and mobile network structures is needed? Here, a fixed