Investigations on Equal Cost Multi-Path Feature in Dynamic Routing Protocols in IPv6 Networks

Worldwide, organizations are gearing up to implement IPv6 in their networks. The main concern of the network architects is the selection of interior gateway dynamic routing protocol for ensuring the best Quality of Service (QoS) support to the users. The available options are RIPng, OSPFv3, EIGRP, and IS-IS. Intelligent routing of packets over multiple paths is performed by ISPs to satisfy guaranteed Service Level Agreement (SLA) imposed network uptimes and QoS. All these protocols support the Equal Cost Multi-Path (ECMP) feature for achieving these objectives. With the ECMP feature providing re-routing in case of link/node failures in multiple path cases, it is worth to investigate its coupling with dynamic routing protocols. Past research work was focused on carrying out performance analysis of the dynamic routing protocols based on QoS and convergence metrics of simple IPv6 networks. In this paper, we present the performance analysis of the IS-IS and OSPFv3 protocols, specifically probing the performance of the ECMP feature in IPv6 networks. 02, 04 and 08 numbers of equal-cost paths between source and destination, are investigated for QoS parameters, using the OPNET simulator. We conclude that IS-IS is the best among the two, supporting ECMP in IPv6 networks with less than 1%, 27%, 43% packet loss ratios in 02, 04, 08 path networks respectively as compared to 7%, 40%, 55% respectively in ECMP coupled with OSPFv3 routing protocol for video traffic, with similar trends for voice traffic, in the discussed scenarios.