Ad-Hoc Networking on Wireless Devices

1
Ad-Hoc Networking on Wireless Devices

• Ben Hilldore
• Advisor Dr. Alvin Lim
• 8/07/2003

2
Goals

• Get Ad-hoc mode working on Zaurus
• Communicate using a multi-hop protocol
• Transfer large amounts of data in an ad-hoc
  environment
• Implement a service oriented ad-hoc network to
  facilitate sensor monitoring and data collection

3
Infrastructure Vs. Ad-Hoc

• Infrastructure
• Centralized network
• Device must communicate through central routing
  points
• Ad-Hoc
• No central structure
• Devices can communicate directly

4
Infrastructure

• Devices must communicate through central point

192.168.0.5
192.168.0.2
192.168.0.1
192.168.0.4
192.168.0.3
5
Infrastructure

• Devices must communicate through central point

192.168.0.5
192.168.0.2
192.168.0.1
192.168.0.4
192.168.0.3
6
Infrastructure

• Devices must communicate through central point

192.168.0.5
192.168.0.2
192.168.0.1
192.168.0.4
192.168.0.3
7
Ad-Hoc

• No centralized structure
• Nodes communicate directly or through
  intermediary node

8
Ad-Hoc

• Example of Ad-Hoc
• .2 wants to send a file to .5

192.168.0.4
192.168.0.2
192.168.0.5
192.168.0.3
9
Ad-Hoc

• Example of Ad-Hoc
• .2 wants to send a file to .5

192.168.0.4
192.168.0.2
192.168.0.5
192.168.0.3
10
Ad-Hoc

• Example of Ad-Hoc
• .2 wants to send a file to .5

192.168.0.4
192.168.0.2
192.168.0.5
192.168.0.3
11
Zaurus SL-5600

• Specs
• 400MHz Intel XScale Processor
• 32MB Ram, 64MB Flash
• Embedix Qtopia
• Embedded Linux
• Comparable to Desktop Linux

12
Zaurus Development

• Compiling on the Zaurus is impractical
• Not enough memory
• Not enough storage
• Embedded Linux does not have many libraries that
  desktop Linux does
• Instead, we cross-compile
• Strong-Arm cross-compiler
• Originally for SL-5500

13
Progress

• Have Zaurus running in Ad-hoc wireless mode
• Successfully cross-compiled Diffusion on to the
  Zaurus
• Simple Diffusion Ping application demonstrates
  multi-hop communication in an Ad-hoc environment

14
Progress Cont.

• Have a service oriented application running on
  Linux PCs.

15
Lookup Server Example
1) File Server Registers with Lookup Server
2) Client Requests File
3) Lookup Server Notifies Client that 192.168.0.5
provides that service
4) Client Sends Request to File Server for File
File Server
5) File Server Sends File
192.168.0.5
192.168.0.5
Lookup Server
192.168.0.2
Client
Client
192.168.0.3
192.168.0.4
16
Conclusions

• Limited librarys for Zaurus makes cross-compiling
  Lookup Server difficult
• New protocol not working
• Develop application to discover nodes in range if
  Diffusion continues to be used

17
Acknowledgements

• Alvin Holting
• Kelly Hout
• Anurag Pujar
• Zaurus Developers Network
• National Science Foundation