A Novel Level-Based IPv6 Routing Lookup Algorithm

Internet migration from IPv4 to IPv6 has introduced more challenge to IP address lookup problem. Nowadays, some existing address lookup algorithms work well for IPv4 addresses, however, few of them can scale well to IPv6 both in lookup and update speed. As IPv6 uses 128-bit addresses, schemes whose lookup time grows with address length become less attractive. In this paper, a novel level based IPv6 routing lookup algorithm, called level-based routing lookup (LRL) algorithm, is proposed. This proposed algorithm is specially designed based on the extensive research on the characteristics of IPv6 prefix length distribution, which is composed of four levels. Different structures are used for different levels. Intensive experiments have been done to evaluate the algorithm. The results show that the new algorithm excels in following aspects: good support of IPv6, extremely excellent fast lookup speed, stable memory consumption and competitive update speed.