SANDS: Specialized Active Networking for Distributed Simulation

We provide an overview of SANDS (Specialized Active Networking for Distributed Simulation), a DARPA-ITO sponsored research project that is using active networking to develop a new approach to real-time, content-based information dissemination. Our approach is based on the use of active interest filtering, a publish/subscribe mechanism that uses active networks technology to install and control dynamically-established content-based filters in intermediate active routers in an IP multicast distribution tree. Active filters prune unneeded information as early as possible in the distribution tree, ensuring that only data desired (i.e., subscribed to) by a receiver actually reaches that receiver. We describe active interest filtering, the per-node algorithms that implement active filtering, and the signaling protocol that installs interest filter state in the active routers. We describe our prototype implementation effort and present measurements from a working prototype that demonstrate the advantages of active interest filtering in a large-scale ModSAF distributed simulation scenario.