Resourceaware Video Multicasting

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Resource-aware Video Multicasting via Access
Gateways in Wireless Mesh Networks
W. Tu, C. Sreenan, C. Chou, A. Misra and S.
Jha (ICNP)
Presented by Xiaoyuan GUO
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Background and Motivation

• Video multicasting has stringent QoS requirements
• E.g. throughput, delay, jitter
• Wireless mesh network (WMN)
• Multi-hop network
• Mesh nodes self-organized, self-configured
• Diversify the capabilities of ad-hoc networks
• Degradation of video quality
• Wireless link throughput limited
• Interference and contention

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Background and Motivation(2)

• Current approaches
• Intra-mesh schemes
• Resources effectively
• Gateway-based routing
• Internet shortcut
• Bottleneck
• Not compare with
• Intra-mesh

• How to get better performance?

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Main Idea

• Limit the depth of wireless multi-hop paths
• Close Intra-mash routing
• Distant gateway-based path

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Challenges and Solutions

• Intra-mesh vs gateway-based path
• Two-tier integrated architecture (TIA)
• Organize group members into a clustered and
  layered architecture
• Avoid busy gateways
• Weighted gateway uploading (WGU)
• Load-distance balanced metric

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Challenges and Solutions(2)

• Decrease interference and contention
• Link-controlled routing tree (LCRT)
• Construct a multicast tree with the least number
  of forwarders per access area
• Alternative channel assignment (ACA)
• Assign different sending/receiving channels to
  successive members alternatively

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Two-tier Integrated Architecture

• Source access area
• S Members
• Area gateways (AG)
• Upload gateway G
• G Gateways

AREA_CONSTRUCTION
JOIN_REPORT
SEARCH
AEARCH_ACK

• Gateway-initiated access area
• Act as S
• Find another access gateway
• Dynamic access area
• Members S/AG

QUALITY_REPORT
TTL/threshold_update
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Performance Evaluation

• Settings
• ns-2 simulator
• RMG vs IM vs EM vs IR
• RMG algorithm with TIA,WGU,LCRT and ACA
• IM algorithm with TIA and WGU
• EM gateway-based routing
• IR intra-mesh routing
• Metric AMT
• AMT average multicast throughput

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Performance Evaluation(2)
Small-scale area
Large-scale area
Gateway Access area size

• Results
• Achieve QoS-guarnateed video multicasting
• Improve scalability of capacity
• Need multiple gateways

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Summary

• Interesting idea
• Employ wired resource while cooperatively
• sharing the intra-mesh bandwidth
• Good Writing Style
• Clear and easy to follow
• How many gateways needed in practice?
• Maybe too many

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Questions and Comments?
Thank you