Energy-Efficient Computing for Wildlife Tracking:
Design Tradeoffs and Early Experiences with ZebraNet
Summary
"Over the past decade, mobile computing and wireless communication have become increasingly important drivers of many new computing applications. The field of wireless sensor networks particularly focuses on applications involving autonomous use of compute, sensing, and wireless communication devices for both scientific and commercial purposes. This paper examines the research decisions and design tradeoffs that arise when applying wireless peer-to-peer networking techniques in a mobile sensor network designed to support wildlife tracking for biology research.

The ZebraNet system includes custom tracking collars (nodes) carried by animals under study across a large, wild area; the collars operate as a peer-to-peer network to deliver logged data back to researchers. The collars include global positioning system (GPS), Flash memory, wireless transceivers, and a small CPU; essentially each node is a small, wireless computing device. Since there is no cellular service or broadcast communication covering the region where animals are studied, ad hoc, peer-to-peer routing is needed. Although numerous ad-hoc protocols exist, additional challenges arise because the researchers themselves are mobile and thus there is no fixed base station towards which to aim data. Overall, their goal is to use the least energy, storage, and other resources necessary to maintain a reliable system with a very high “data homing” success rate. We plan to deploy a 30-node ZebraNet system at the Mpala Research Center in central Kenya. More broadly, we believe that the domain-centric protocols and energy tradeoffs presented here for ZebraNet will have general applicability in other wireless and sensor applications.”[1]
Discussion
• Will the collar itself produce any changes in the behavior of the zebras?
It is possible that if the final design of the collar is noticeable the zebras carring it would have acceptance issues within the harem.

• Is there a predefined time at which the information will be transfered between nodes?
They used four communication phases that occured withing 30 minues every two hours over the entire month.

• Did they conclude about which protocol is the best for this research?
No, they did some simulation but they didn't give any definitive information about the final decision in terms of protocols.

• Does their experiment model what they want?
If testing the protocols with different radion ranges was the goal of their experiment (it is not clearly stated in the paper) the answer is yes. But if the goal was to test including the final characteristics, then the answer is not, there is important information that was left out in their experiments, like temperature, biometric data and so on.

• What other animals could be fitted with this sensors?
I'd have to be an animal big enough to carry the collar and one that cannot take the collar of.
References
• Philo Juang, Hidekazu Oki, Yong Wang, Martonosi Margaret, peh Li-Shiuan and Rubenstein Daniel, "Energy-Efficient Computing for Wildlife Tracking: Design Tradeoffs and Early Experiences with ZebraNet". October 2002, Princeton University
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