Technique to eliminate sorting in ip packet forwarding devices

Abstract

This paper will present a solution to eliminate the requirements of sorting by prefix length in IP forwarding devices using Ternary Content Addressable Memories (TCAMs). This will do away with delays arising from inserting into a sorted list. To achieve this, the routing table entries in the TCAM are split by output port. This solution requires slight modifications to current TCAMs including the elimination of the built-in encoder. Overall, the solution presented reduces the insertion problem to lookup speed while maintaining similar clock rates and storage requirements of traditional TCAMs.

Eliminating Sorting in IP Lookup Devices using Partitioned Table

“…Many routers now include a co-processor to perform the crucial task of IP lookup. This paper is a continuation of work for a previously proposed design of an IP lookup co-processor [10]. This paper is organized as follows.…”