Title
A Specialized Static Content Addressable Memory For Longest Prefix Matching In Internet Protocol Routing
Abstract
An internet protocol (IP) router forwards packets based on their destination address by finding the longest matching prefix in internal lookup tables. In this paper, a fully static CAM that directly determines the next hop among the stored addresses is described. The proposed design achieves high lookup throughput, optimal memory utilization, integrated priority encoding, and high power efficiency. The proposed address look up architecture is 81.2% more energy efficient than a TCAM implementation while achieving 1.6x higher operating frequency. The proposed CAM uses 67.2% less energy than a previous dynamic internet protocol CAM (IPCAM) design. Simulations carried out using a bulk CMOS 65-nm foundry process show the proposed IPCAM circuits can operate above 1 GHz. With dynamic voltage scaling to V-DD = 0.6 V, the proposed design uses 0.85 fJ/bit/search at speeds adequate for 10 G Ethernet requirements. The all static design is amenable to automated circuit design flows, as demonstrated by porting to a commercial 45-nm cell library implementation, and can be pipelined. Finally, the proposed circuit architecture is shown to be scalable to IPv6.
Year
DOI
Venue
2011
10.1166/jolpe.2011.1142
JOURNAL OF LOW POWER ELECTRONICS
Keywords
DocType
Volume
Associative Memories, Router, CIDR, IPv4, Internet Protocol (IP) Routing, Longest Prefix Match, Content Addressable Memory (CAM), Ternary CAM (TCAM), Priority Encoder, IPv6, Scalability
Journal
7
Issue
ISSN
Citations 
3
1546-1998
0
PageRank 
References 
Authors
0.34
0
2
Name
Order
Citations
PageRank
Satendra Kumar Maurya151.54
Lawrence T. Clark215533.27