Packet aware transport for metro networks

Today\´s metro networks have evolved from the need to support traditional voice and private line services and were optimized to support time division multiplexing (TDM) services. However, the growth of private line services is dominated by the access (also called "backhaul") to packet switches that provides frame relay, ATM, IP and Ethernet services. This paper provides a coherent architectural vision for metro access networks, which the author calls the packet-aware transport network (PATN). The PATN is designed to support the packet and TDM transport within metro areas in a scalable manner, and interfaces the inter-city packet and TDM transport backbone networks. Since the PATN supports the IETF pseudo-wire encapsulation (PWE) schemes for all packet access traffic, it is synergistic with the move towards a converged MPLS-based multi-service packet backbone network.