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Greedy Prefix Cache for IP Routing Lookups

Author:

Zhuo Huang, Gang Liu, Jih-Kwon Peir

Publisher:

I-SPAN 2009

Presenter:

Hsin-Mao Chen

Date:2010/03/10

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Outline

IntroductionMinimal Expansion PrefixMotivation For Caching Parent PrefixGreedy Cache With Prefix UpgradePerformance Evaluation

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Introduction

0100

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Minimal Expansion Prefix

Suppose the deepest that the key can traverse in the trie is i bits and the last remembered prefix node is a parent P. If the resulting i+1 bit prefix is the shortest disjoint child of the matching parent that also matches the given key. It can be used to partially represent P.

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Minimal Expansion Prefix

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Motivation For Caching Parent Prefix

Trace from MAWI[18] and the as1221 routing table[3]

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Motivation For Caching Parent Prefix

The results indicate that caching the parent prefix is much more efficient than caching the MEPs since it requires several MEPs to cover a parent prefix.

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Greedy Cache With Prefix Upgrade

Instead of the MEP, the parent prefix can be cached when all the children prefixes are also present in the cache.

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Greedy Cache With Prefix Upgrade

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Greedy Cache With Prefix Upgrade

The prefix upgrade mechanism may not always upgrade an existing MEP to a parent prefix if the parent has more than one child.

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Greedy Cache With Prefix Upgrade

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Performance Evaluation

MAWI[18] and the as1221 routing table[3]

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Performance Evaluation

Fully-associative

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Performance Evaluation

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Motivation For Caching Parent Prefix