Implementing the Orwell protocol over a fibre-based high-speed ATMnetwork

Asynchronous transfer mode (ATM) has emerged as a possible contender for the next generation switching system and fundamental transport basis for the broadband integrated services digital network (B-ISDN) and telecommunications in the future. It is widely thought of as the network to accommodate the uncertain requirements of future public communications because of its high degree of flexibility and service independency. The Orwell protocol developed by British Telecom can provide a communication base to meet the requirements of such a network. Orwell is used as a slotted ring protocol designed to carry a mixture of services which form the basis of an ATM network. The authors describe the realisation of a 155.52 Mbit/s fibre-optic physical layer from the Orwell protocol based on an ATM technology, and also discuss how the Orwell protocol can offer broadband transport capabilities and can provide access to and interwork with existing networks, such as telephone networks and 64 kbit/s based ISDNs