University of Nevada, Reno

Virtual Direction Multicast for Overlay Networks

Suat Mercan & Dr. Murat Yuksel

HOTP2P’11

Outline

• Introduction• Virtual Directional Multicast• Simulation Results

Introduction

Motivation• Increasing bandwidth (127 Kbps(2000) 4.4 Mbps(2010))

• Increasing Internet usage 360,985,492(2000) - 1,966,514,816 (2010)

• High demand for multimedia applications (Internet TV, tele-conference, online education, youtube)

• A huge amount of internet traffic coming from multimedia (26% of Internet traffic)

Delivering Content to Users

• Client/Server Architecture • Content Delivery Networks (CDNs) Akamai• Network Layer Multicast (IP multicast) IPTV• Application Layer Multicast (ALMs) P2PTV

Application Layer Multicast• Implemented at application layer• Packets are replicated at end-hosts• Easy to deploy• Infrastructure independent• Adaptable to network changes

Virtual Direction Multicast (VDM)

Virtual Direction Multicast

• Tree based• Source is alone at the beginning• Tree extends with new joins. • Want to use minimum resource

Directionality

P C P C P C

CASE I CASE II CASE III

Join

CASE I

Join

CASE III

CASE I

Join

CASE III

CASE II

Scenarios

2 Case II 2 Case III Case II and Case III

Scenario1

Scenario2

Scenario3

Reconnection

• Each node knows its grandparent• When parent leaves start join process at grandparent

Generalizing Virtual Distance

• Round Trip Time (RTT) is used to calculate distances• What about loss rate?• Target specific application

Simulation Results

Closest Node Multicast (CNM)

• Use closeness• A node choose closest node to join

Simulation Setup

• NS-2 (Network simulator)• 792 nodes in physical network• 200 nodes in overlay network• Degree of each node between 2-5• Run 10000s• First 2000s for join process• Under different churn rates(1% - 20%)• Run each simulation 32 times

Performance metrics

Stress

Performance metrics

Stretch

Performance metricsOverhead

Loss

Simulation Results

Stress

Simulation Results

Stretch

Simulation Results

Overhead

Simulation Results

Loss

Conclusion

Summary

• Motivation Efficient data distribution multimedia applications

• Virtual Directional Multicast Aims to reduce resource usage and to increase user

satisfaction

• Simulation Results