• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.5B
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• pp.285-295
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• 2008

Internet routers perform packet forwarding which determines a next hop for each incoming packet using the packet's destination IP address. IP address lookup becomes one of the major challenges because it should be performed in wire-speed for every incoming packet under the circumstance of the advancement in link technologies and the growth of the number of the Internet users. Many binary search algorithms have been proposed for fast IP address lookup. However, tree-based binary search algorithms are usually unbalanced, and they do not provide very good search performance. Even for binary search algorithms providing balanced search, they have drawbacks requiring prefix duplication. In this paper, a new binary search algorithm which provides the balanced binary search and the number of its entries is much less than the number of original prefixes. This is possible because of composing the binary search tree only with disjoint prefixes of the prefix set. Each node has a prefix vector that has the prefix nesting information. The number of memory accesses of the proposed algorithm becomes much less than that of prior binary search algorithms, and hence its performance for IP address lookup is considerably improved.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.12C
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• pp.1642-1651
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• 2004

Advance of internet access technology requires more internet bandwidth and high-speed packet processing. IP address lookups in routers are essential elements which should be performed in real time for packets arriving tens-of-million packets per second. In this paper, we proposed a new architecture for efficient IP address lookup. The proposed scheme produces multiple balanced trees stored into a single SRAM. The proposed scheme performs sequential binary searches on multiple trees. Performance evaluation results show that p개posed architecture requires 301.7KByte SRAM to store about 40,000 prefix samples, and an address lookup is achieved by 11.3 memory accesses in average.