The 2007 paper entitled ldquoSwarming Network for Intruder Detectionrdquo described the concept for an intruder detection and tracking sensor network that exhibits swarming behavior. The network is based on simple signals and cueing with no data protocols as a means to minimize cost and complexity. Further, a means to detect an intruder via measuring the blockage by the intruder of randomly placed illumination signals was also described. Preliminary calculations indicated the potential for high probability of detection and low probability of false alarm. This paper describes the results of further investigation, including preliminary design to better estimate affordability and scalability, and analysis and experiments to explore the assumptions of the tone-based signaling approach. Results to date build confidence that the concept is realizable.