Concept of Virtual Path Hopping to Improve QoS and Reliability of Connection-oriented Networks

Abstract

The QoS provided by today's best effort Internet is not good enough for real-time premium traffic. It is believed that the QoS guarantees of the Internet could be better provided by connection-oriented networks. IP/MPLS is one such technology and these connection-oriented networks are inherently more vulnerable to network failures. Network failures can broadly be classified into two types, ie., link/path and degraded failures. Degraded failures that account for about 50% of total failures are detected by control-plane timers. The control plane and the data plane of IP/MPLS networks are logically separated and therefore a failure in the control plane should not immediately terminate communications on the data plane. The Virtual Path Hopping (VPH) concept proposed in this study distinguishes these degraded failures from link/path failures and avoids the terminations of data communications on the data plane that are due to these degraded failures. It changes the traffic carrying a degraded VP to a new VP in a predetermined VP-pool before the control-plane timer expires due to degraded failure. This paper discusses the concept of VPH and its numerous advantages such as load balancing, traffic distribution, and the ability to support dual-failure situations. Computer simulations were conducted and the results are presented to support the concept of VPH.