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Efficient Packet Classification using Splay Tree Models

Author:

Srinivasan.T, Nivedita.M, Mahadevan.VPublisher:

IJCSNS International Journal of Computer Science and Network Security 2006

Presenter:

Hsin-Mao Chen

Date:2010/05/19

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Outline

IntroductionSplay TreesST-PC TechniqueSearchComplexity Analysis

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Introduction

Splay Tree based Packet Classification (ST-PC)

1. Splay tree

2. Prefix conversion

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Splay Trees

Splay trees are self-balancing or self-adjusting binary search trees.

When we access a node of the tree (retrieval, insertion, deletion), it performs radical surgery on the tree.

Splay trees does not require height or balance factors as in AVL trees and colors as in Red-Black trees.

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Splay Trees

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Splay Trees

There are six rotations possible in a splay tree:

1. Zig Rotation2. Zag Rotation3. Zig-Zig Rotation4. Zag-Zag Rotation5. Zig-Zag Rotation6. Zag-Zig Rotation

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Splay Trees

g

p

x

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Splay Trees

Zig Rotation

p

x

a b

c

x

a

b c

p

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Splay Trees

Zig-Zig Rotation

g

p

x c

d

a b

x

a

b g

p

c d

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Splay Trees

Zig-Zag Rotation

g

p

a x

d

b c

p

a b

g

c d

x

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ST-PC Technique

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ST-PC Technique

[0 ,15]

[16,16]

[17,31]

[32,32]

[33,47]

[48,63]

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ST-PC Technique

[0 ,15]

[16 ,16]

[17 ,31]

[32,32]

[48,63]

[33 ,47]

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ST-PC Technique

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Search

[17 ,31]

[0 ,15]

[33 ,47]

[16 ,16] [32,32]

[48 ,63][0 ,15]

[16 ,16]

[17 ,31]

[33 ,63]

F5, F6

[32 ,32]

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Complexity Analysis

Binary Trie:

All the prefix are distinct: 2k+1-1

All k bits of each of the r rules are distinct: (k * r)+1 Splay Tree:

All the prefix: 2k

All rule are distinct: 2*r

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Complexity Analysis

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Complexity Analysis

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Complexity Analysis

m unique accesses

Binary Trie: m*log(2n)

Splay Tree: m*log(n)

(m-t) unique accesses

Binary Trie: m*log(2n)

Splay Tree: ((m-t)log(n)) + t*log(β)

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Complexity Analysis

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Complexity Analysis