Power Efficient and Fast Updating Approach for TCAM-Based Forward Engine

Abstract: Ternary Content-Addressable Memories (TCAMs) are becoming popular for designing high-throughput forwarding engines on routers. They are fast, cost-effective and simple to manage. However, a major drawback of TCAMs is their large power consumption. This paper presents architectures and algorithms for making TCAM-based routing table more power efficient. The proposed architecture and algorithms are simple to implement, use commodity TCAMs, and provide worst- case power consumption guarantees (independent of routing table contents). The most existing TCAM-based forwarding engines involve shifting TCAM entries when the forwarding table is updated, typically incurring a lengthy update duration. And also proposed a TCAM-based longest prefix forwarding engine with fast updating. The key idea behind the design is to maintain the forwarding table in a TCAM according to the Minimum Independent Prefix Set.

Keywords: TCAM, Delay, Network algorithm, memory architecture, bit selection, prefixes.