## Fast address lookup for Internet routers (1998)

Venue: | IEEE Broadband Communications |

Citations: | 79 - 4 self |

### BibTeX

@INPROCEEDINGS{Nilsson98fastaddress,

author = {Stefan Nilsson and Gunnar Karlsson},

title = {Fast address lookup for Internet routers},

booktitle = {IEEE Broadband Communications},

year = {1998},

pages = {11--22},

publisher = {Chapman & Hall}

}

### Years of Citing Articles

### OpenURL

### Abstract

We consider the problem of organizing address tables for internet routers to enable fast searching. Our proposal is to to build an efficient, compact and easily searchable implementation of an IP routing table by using an LC-trie, a trie structure with combined path and level compression. The depth of this structure increases very slowly as function of the number of entries in the table. A node can be coded in only four bytes and the size of the main search structure never exceeds 256 kB for the tables in the US core routers. We present a software implementation that can sustain approximately half a million lookups per second on a 133 MHz Pentium personal computer, and two million lookups per second on a more powerful SUN Sparc Ultra II workstation. 1

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Citation Context ...ure contains five pointers and one index. More general but slightly dated works on Gb/s routers that could be of interest to the reader are presented in [3, 14, 16]. 3 LEVEL-COMPRESSED TRIES The trie =-=[7]-=- is a general purpose data structure for storing strings. The idea is very simple: each string is represented by a leaf in a tree structure and the value of the string corresponds to the path from the... |

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Citation Context ...herefore place our proposal in relation only to the three most recent works from the literature. Our search structure and implementation is akin to and has been inspired by the work of Brodnik et al. =-=[4]-=-. They use a different data structure from ours and are concerned with the size of the trie to ensure that it fits in a processor's on-chip cache memory. As a consequence, it is not immediately clear ... |

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Citation Context ...t in practice, since it often gives a significant overall size reduction. One might think of path compression as a way to compress the parts of the trie that are sparsely populated. Level compression =-=[1]-=- is a recently introduced technique for compressing parts of the trie that are densely populated. The idea is to replace the i highest complete levels of the binary trie with a single node of degree 2... |

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Citation Context ...timum performance. The nodes of the trie structure contains five pointers and one index. More general but slightly dated works on Gb/s routers that could be of interest to the reader are presented in =-=[3, 14, 16]-=-. 3 LEVEL-COMPRESSED TRIES The trie [7] is a general purpose data structure for storing strings. The idea is very simple: each string is represented by a leaf in a tree structure and the value of the ... |

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Citation Context ...timum performance. The nodes of the trie structure contains five pointers and one index. More general but slightly dated works on Gb/s routers that could be of interest to the reader are presented in =-=[3, 14, 16]-=-. 3 LEVEL-COMPRESSED TRIES The trie [7] is a general purpose data structure for storing strings. The idea is very simple: each string is represented by a leaf in a tree structure and the value of the ... |