Mesh Networking Case Studies COTS

1
Mesh Networking Case Studies (COTS)

• Technology For All Houston, Texas (non-profit)
• Mesh network for low income residences,
  libraries, and small businesses

• Fastline Internet Vivian, Louisiana
• Bypassed by cable and DSL
• Mesh network with tiered pricing for bandwidths
  of 64 kb/s to 1 Mb/sec (10/mo to 60/mo)
• Research Testbeds (IITK, Microsoft, MIT, Rice, )
• And many more

2
COTS Platforms

• Provide experience in real-world environments
• Measurements to drive our design
• Identify new challenge areas
• Experiment with some protocols (rate control,
  routing, ...)
• Limits
• PHY/MAC not modifyable (or can only be slightly
  tuned)
• TAPs performance goal
• 100 Mb/sec to leapfrog wireline technologies and
  enable new applications
• Clean-slate design

3
Why Clean Slate Design?

• Critical differences mesh vs. ad hoc networks
• Mesh APs are non-mobile powered infrastructure
• Their placement is planned vs. random
• Traffic matrices are not uniform random
• Per-user, per-time performance critical
• A starved user or poor route could last
  indefinitely
• Architecture, service model, ownership model,
  security,
• WLAN, like mesh is infrastructure. Critical
  differences
• Mesh APs are not wired, are outdoors,

4
Why Clean Slate Design?
Scenario changed fundamentally from cellular, ad
hoc, WLAN,
Architecture, Protocols, PHY Change
Fundamentally
5
Research Challenges

• Physical layer
• Achieve 100s of Mb/s among TAPs (MIMO!)
• Media access
• Target multi-hop and exploit PHY capabilities
• Fairness and traffic control
• With TCP/WiFi, nodes farther away from wires get
  much less bandwidth and can starve
• Prototypes, Testbeds, and Measurement Studies
• Platforms for experimentation and proof-of-concept

6
Rice TAP Platform

• 400 Mb/sec via 4x4 MIMO custom design
• Non line of sight
• Single 2.5 GHz WiFi channel and 20 bits/sec/Hz
  efficiency
• Custom MAC design and FPGA implementation