Smaller, faster, and cheaper sensors resulted from continuing advances in sensor, semiconductor, and communication systems technology makes it possible to have real sensor intensive networks of fixed and mobile devices for use in many in-door and out-door applications. Several sensor network testbeds have been developed, but none of them consider how to incorporate smart sensor capability in the system. In this paper, we describe the design and implementation of a testbed, ToSS (Testbed of Smart Sensors), developed in collaboration with NASA Stennis Space Center for testing and verifying IEEE 1451-compatible sensor systems with network performance monitoring capability for space shuttles and other space exploration relevant tasks. © 2007 IEEE.