Cross-layer Design in Wireless Mesh Networks

[seminar class]

Introduction to the Wireless Mesh Networks
Mesh Routers:
•Infrastructure
•Almost stable
•No power limitation
•Multiple Wireless Interface
•Routing/Bridge/Gateway
Mesh Clients:
•Mobile
•Battery powered
•One Wireless Interface
•Routing
Motivation of Cross-layer design
lUnreliable of physical layer:
• Various wireless technology
IEEE 802.11,802.16,3G
various capacity, bit error rate
• Advanced physical technology
Multiradio/multichannel, directional antenna, MIMO
Conclusion1: MAC, routing, and transport protocols have to work
together with the physical layer.
Motivation of Cross-layer design lMulti-hop:
• Accumulated effect
Performance degradation
• Local vs. Global optimization
MAC layer vs. Routing, Transport layer A
Conclusion2: MAC, routing, and transport protocols need to work
collaboratively among themselves
Cross-layer Design Schemes
According to the relationship of different layers:
1. Loosely-coupled
Use parameters in other protocol layers
• Don’t totally abandon the transparency between layers
• Limited improvement
2. Tightly-coupled
Different layers are optimized together
Extreme: merge different protocol layers into one layer
• Better performance
• Lose protocol layer abstraction


Download full report
http://asiafimeeting/2008/presentations/2-20/PDF-web/Wenjie%20Hu.pdf