Powerpoint template for scientific poster

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DuraNet Energy-Efficient Durable Slot-Free
Power Scheduling Terence Tong, David Molnar, and
Alec Woo UC-Berkeley

• Goals
• Energy conservation
• Minimize idle listening
• Reliable
• Issues
• Density, Scale, Clock skew, Joins / Leave
• Queue Overflow, Aggregation
• Simple
• Distributed, Low memory footprint
• Protocol Details
• Sync Phase
• Schedule Negotiation
• Hidden Node Problem, Backoff on RTS
• Buffer Queue Problem, RTS/CTS abort
• Sequence Number Protocol
• Backoff

• Problem
• Tiny low-power devices for sensing environment
• Data collection, Pursuer/Evader applications
• Berkeley Mica2 mote platform
• 8-bit 8MHz Atmel processor, ChipCon 1000 radio
• Must conserve energy and extend battery lifetime
• 2 AA batteries 2000 mAh, lasts for 7days if
  node leaves idle
• Cant replace batteries every 7 days
• Schedule Negotiation

• Simulation Methodology
• TOSSIM, TinyOS 1.1 w/Blast routing
• Fixed MT topology on grid
• Periodic synthetic workload

C-gtP Blah Blah Blah P-gtC ACK
C Lets Talk P Come by 6 everyday

• Conclusions
• Can build near-optimal schedules at low cost
• Overall savings depends on schedule durability
• Increase durability with parent ACK
• Factors affecting durability
• Clock Skew do time sync in ACK
• Link Reliability retransmit
• Interference Neighborhood Change
• Need experiment to determine real rate of change