Recursively Partitioned Static IP Router Tables Author: Wencheng Lu,Sartaj Sahni Publisher: IEEE TC,2010 Presenter: Jia-Wei Yo Date: 2011/09/14 1

Introduction Propose a method to partition a large static router table into smaller tables using a structure, such as a multibit trie (MBT) or a hybrid shape shifting trie (HSST). Reduce ◦ Total memory requirement ◦ Worst case number of memory accesses 2

Recursive Partitioning 3

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Incorporating Leaf Pushing The worst-case number of memory accesses required for a lookup maybe reduced using controlled leaf pushing Assuming that the original prefix set contains the default prefix, the stated inheritance ensures that every search in a partition finds a matching prefix and hence a next hop. 7

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Optimization 9

auxiliary partitions are restricted to be represented by base structures 10

Implementation For benchmarking purposes, we assumed that the router table will reside on a QDRII SRAM (dual burst), which supports the retrieval of 72 bits of data with a single memory access. We considered two hash table designs—36 and 72 bits. 11

Experimental Result 12

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