Projecting IPv6 Packet Forwarding Characteristics Under Internet-wide Deployment

While routing table growth, its impact, and causes have been examined extensively for IPv4, little work in this direction exists for IPv6. This paper is the first step at examining performance aspects of IPv6 packet forwarding. We do so by using a software implementation of various packet forwarding algorithms used by routers and running them against IPv6 tables. In the lack of a wide deployment of IPv6, we generate IPv6 routing entries based on IAB allocation recommendations. We simulate growth of routing tables due to new prefix allocations and under partial deployment scenarios. Additionally, we consider factors that inflate routing table sizes artificially. These include load balancing, multihoming, and failure to aggregate aggregatable prefixes. We conclude that if modern routers were to simply replace their IPv4 prefixes with an equivalent number of IPv6 prefixes, without changing anything else, an average lookup in the routing table will be 67% more expensive. Further, the IPv6 routing table will require at least 4.5 times more memory to store the same number of prefixes.