IP lookup using Minimal Perfect Hashing

Abstract

IP lookup plays a significant role in networking. The rapid development of the Internet brings new challenges to IP lookup in recent years. To deal with these challenges, we propose the first algorithm that we are aware of to use Minimal Perfect Hash (MPH) filters in IP lookup. It achieves the information theoretic optimum on-chip memory storage and O(1) worst case on-chip lookup speed. To overcome the shortcoming of MPH filter's no support for insertions, we propose an incremental update algorithm which achieves average update speed of O(1) memory access per update.