Distributed optical frame synchronised ring, an efficient multi-service packet network

The convergence of datacom and telecom services together with the emergence of broadband subscriber access lines have created new challenges for metropolitan area networks (MAN). However, the legacy access and transport systems are not being teared down but remain operational as long as they generate revenue. Thus a competitive MAN architecture should be capable of supporting multiple services as well as a wide variety of access network technologies. While the main issue usually is to find the cheapest solution, there are many other important requirements that cannot be discarded. To be successful a MAN should guarantee both subscriber satisfaction and efficient network management. Only in this way the operator can offer attractive services to the customers and avoid spending all his turnover to keep the network running. There are many ways to identify the system requirements for different kinds of networks. One way is to find out the fundamental requirements of the services and the needs of users and network operators. Only after these aspects have been studied, different network technologies and protocols should be evaluated to find out how they can be used to meet the requirements. If the process is conducted in the opposite way, the system may not be able to efficiently meet all real life requirements.In this paper the requirements for future MAN are lined out and an efficient solution based on ring structured slotted network is proposed. Furthermore, the early prototype systems and the future plans are explained.