Algebra and algorithms for QoS path computation and hop-by-hop routing in the

internet

Outline

• Introduction and Contribution• An algebra for QoS path problems• QoS path computation• QoS Hop-by-hop routing• QoS Multirouting

Introduction

• Shortest path routing: Dijkstra’s Algorithm• Hop-by-hop routing: local, depending on

destination only• For QoS, both have limitations

• Contribution1) Revise Dijkstra’s algorithm2) Eliminate loop in hop-by-hop routing

An algebra for QoS path problems

Notations

QoS path computation

• Lexicographic-lightest path

• S-lightest path

A generalized Dijkstra’s Algorithm

QoS Hop-by-hop routing

• Nonoptimality When Isotonicity Fails