• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11B
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• pp.911-919
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• 2004

IP address lookup is one of the essential functions on internet routers, and it determines overall router performance. The most important evaluation factor for software-based IP address lookup is the number of the worst case memory accesses. Binary prefix tree (BPT) scheme gives small number of worst case memory accesses among previous software-based schemes. However the tree structure of BPT is normally unbalanced. In this paper, we propose weighted binary prefix tree (WBP) scheme which generates nearly balanced tree, through combining the concept of weight to the BPT generation process. The proposed WBPT gives very small number of worst case memory accesses compared to the previous software-based schemes. Moreover the WBPT requires comparably small size of memory which can be fit within L2 cache for about 30,000 prefixes, and it is rather simple for prefix addition and deletion. Hence the proposed WBPT can be used for software-based If address lookup in practical routers.

• 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.