Characterizing and Conserving Energy Consumption in Mobile P2P Systems Selim Grn, Priya Nagpurkar, a

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Characterizing and Conserving Energy Consumption
in Mobile P2P SystemsSelim Gürün, Priya
Nagpurkar, and Ben Zhao Department of Computer
Science, U.C. Santa Barbara
Stargate and Our Evaluation Bench
Breaking News
Chimera A Light-Weight P2P Protocol
In Challenging iPod, Microsoft Hustles, Samsung
Stutters

• Light-weight, structured P2P protocol based on
  Tapestry
• Developed in UCSB-CURRENT lab
• Implemented in C as an application library
• Easy to port Requires (only) OpenSSL, arm-gcc is
  fine!
• Chimera-CHAT
• A generic, command-line based chat application
• Forwards messages based on destination hosts
  node identifier
• Chimera Internals
• Borrows many concepts from Tapestry, e.g.
  circular address space
• Prefix based routing O(log(n)) hops in average
• Nodes keep links to nodes in close proximity for
  stability

.... The U.S. software maker also boasted that
Zune has what iPod doesnt have, music-sharing
capability. Using its Wi-Fi wireless function,
Zune users will be able to detect one another and
then share songs, recordings and pictures
wirelessly. ..
By Cho Jin-seo, Staff Reporter September
15, 2006

• How to implement P2P applications/routing stacks
  on resource-constrained mobile devices?

Wireless Card Sleep Policy
Can we use Chimera network manager for better
energy savings?

• Underlying Research Questions
• What are the resource constraints of mobile
  devices and what makes P2P more challenging on
  such devices?
• How do current P2P protocols utilize mobile
  device resources, especially the limited energy
  supply
• Can we implement a mobile-friendly,
  energy-efficient P2P application on such devices?
  How?

Chimera Energy Consumption Results

• CPU utilization is low
• We do not observe any significant increase in CPU
  load when we increase network size from 25 nodes
  to 200
• Techniques like voltage/clock scaling can reduce
  CPU energy consumption significantly
• Analyzes with much larger networks pending!
• Wireless utilization is also low
• Idle 70 of the time, in average
• Better utilization of wireless interface needed
• Compared results to TMSNC
• A command line based MSN client
• Not a substantial difference

Wi Wireless Idle time Wt Wake up timeouts for
checking network state
Future Directions

• Our Goal A resource-aware, energy efficient P2P
  protocol
• Tapestry like, Java based implementations not
  suitable for mobile platforms
• Chimera Surprisingly efficient!
• Physical layer power saving protocols useful but
  not enough!
• More savings possible with more feedback from P2P
  protocol layer to physical layer.
• A lot of work is ongoing
• Compare power saving methods
• Evaluate in much larger mobile communities