The Research And Realization Of PWE3 For ATM Cell Transfer

As the main backborn network in the last twenty yeas for the ISP, ATM has been the main technology for a lot of profitable services. It can offer sufficient QoS for the traffic, but the traditional ATM network is difficult to be upgraded, extended and it's hard to communicate with other network services. With the development of the IP/MPLS, "everything over IP" and "everything is IP" become more and more important. The IP network has good extension, upgrade and compatible ability, so it has been used by the ISP to develope their new services. But the solution must be found to maintain the traditional profitable ATM services and to extend the new IP services. PWE3 maybe the most appropriate approach to this problem.This paper introduces the PWE3 firstly. The related IETF work group defined the network protocols for PWE3, and also gave the functionsa and the details of realization for the PWE3 are different, they also gave the performance and the details of realization of PWE3. PWE3 is based on the Packet Swith Network, which may be IP or MPLS network. The following sections of the paper give the realization of PWE3 on the MPLS network, which uses LDP as the signaling. To realize the PWE3, we have extended the LDP. The most important work of this paper is to realize the ATM CELL TRANSFER over the PWE3. The last two sections give the realization and verification in details, including the protocol extension and the different realization methods.This paper offers a good solution for the ISP to develope their network services from traditional ATM to IP/MPLS. As a new conception, PWE3 has a good extension space, and more and more work needs to be done to make it grow up. This paper may be useful for PWE3's development.