An improved architectural approach for implementation of a low power, scalable topology for a software defined radio (SDR). Low power processors and switching elements forming building blocks are employed in an embedded switched fabric architecture network having a repeating building block topology that advantageously employs wormhole routing and has self-healing, fail-safe properties. Differential signaling is used and data rates in excess of 250 Mbps are possible. In one embodiment a dual civilian and military channel SDR is disclosed; in other embodiments, a plurality of independent SDR channels, with or without encryption, are disclosed. A plurality of different topologies are disclosed including torodial topologies having a planar topology with orthogonal connections, a planar topology with orthogonal and diagonal connections, and a cube topology with both orthogonal and/or diagonal connections.