Minerva: distributed tracing and debugging in wireless sensor networks

Development of wireless sensor network applications remains a challenge, due to lack of visibility into the global network state. Debugging instrumentation using printf-like instructions affects the execution timing and non-intrusive approaches, such as JTAG, have not been used beyond a single node due to their high cost.

This paper presents Minerva, a testbed architecture for distributed debugging of wireless sensor networks. At the core of our architecture is a flexible debug board installed at each node. The board design is driven by cost-efficiency of the testbed instrumentation and provides access to the on-chip debug port of the sensor node's processor. We focus on three main debugging modalities: (i) non-intrusive network-wide tracing of the internal state of individual nodes; (ii) synchronous stopping of the whole network on a breakpoint; and (iii) distributed assertion checking. We demonstrate the debugging capabilities of Minerva in use-cases based on well-known sensor network protocols in a 20-nodes indoor testbed. Our results indicate that Minerva provides non-intrusive, network-wide debugging of sensor network applications at a low cost.