Efficient location of free spaces in TCAM to improve router performance: Research Articles
Weidong Wu, Bingxin Shi, Feng Wang · International Journal of Communication Systems · 2005
A ternary content-addressable memory (TCAM) is a popular hardware device for performing fast IP-address lookup. Because keeping all entries sorted in TCAM, we need move the entries for inserting a new entry. In this paper, we have presented a scheme for minimizing route update overheads in TCAM-based forwarding engines. Our optimizations are based on the hierarchy of prefixes in the routing table. The number of memory movement per update depends on the sequence of the new-inserted prefixes, instead of the initial prefixes in routing table. For the real route update traces, the average number of movements is less than 0.01. Further, when compared to an existing optimization algorithm, in the average case, our algorithm shows a 90p reduction in movement overheads. Copyright © 2005 John Wiley & Sons, Ltd.