Bug-tolerant sensor networks: Experiences from real-world applications

Abstract

Typical sensor networks include large number of motes deployed outdoors. The users expect these networks to work several months or years without maintenance. As a result, every mote must operate reliably for a long time, and it puts a high stress on both hardware and software. Therefore, programs running on motes cannot suffer from software bugs, and the developers must fix them before the deployment. In this work, we summarize the major techniques for fixing software errors in protocols and applications for sensor networks. However, some bugs are hard to find in the lab, as they do not occur in testing conditions. Therefore, our motes include self-healing techniques, which detect and deal with software problems in the runtime. By doing so, motes keep working reliably for a long time, even when developers did not fix all bugs before the deployment. For instance, we failed to fix a few software errors in the MAC protocol, but the self-healing approach allowed motes to work several weeks outdoors.