ECHO: Efficient Zero-Control-Packet Broadcasting for Mobile Ad Hoc Networks

Applications such as collaborative mapping motivate a need for network-wide broadcasting in Mobile Ad Hoc Networks (MANET) with low-rate long-range links. Existing MANET protocols are inadequate in such low-capacity regimes due to their high use of control packets. We present a novel protocol called ECHO that constructs and maintains a broadcast backbone without using any control packets. Instead, using a field in the data packet header, a node transmits and listens for an “echo” of the specific packet to determine its membership in the backbone. ECHO is deterministic, source-independent, fully distributed, accommodates mobility, and balances battery consumption across nodes. We prove ECHO’s correctness and show that its communication complexity is lower than that of Multi-Point Relay (MPR) and Flooding, and comparable to that of Opportunistic Announcement (OA). Simulations over random mobile low-capacity networks show that ECHO provides at least a 30 percent better delivery ratio than Flooding, MPR, and OA for 50-node networks and dramatically reduces the communication load. Experiments on a 12-node testbed of goTenna mobile mesh networking devices show that ECHO reduces transmissions by about 3x and increases battery life by more than 50 percent over Flooding. ECHO’s performance advantages are crucial for scalable broadcast in low-power, low-capacity wireless networks.