Date Added: Jan 2012
Wireless reprogramming of sensor nodes is an essential requirement for long-lived networks since the software functionality changes over time. The amount of information that needs to be wirelessly transmitted during reprogramming should be minimized since reprogramming time and energy depend chiefly on the amount of radio transmissions. In this paper, the authors present a multi-hop incremental reprogramming protocol called Zephyr that transfers the delta between the old and the new software and lets the sensor nodes rebuild the new software using the received delta and the old software. It reduces the delta size by using application-level modifications to mitigate the effects of function shifts.