Scalable Multipath Exploration in Ad-Hoc Networks

Multipath routing allows for a reliable communication in ad-hoc networks, e.g., to transport VoIP calls in disaster scenarios. Due to the usage of different paths in conjunction with Forward Error Correction, failures can be tolerated without interrupting real-time transmissions. However, current multipath algorithms either depend on global topology information, perform an excessive message flooding, or require information of physical node positions. The situation becomes even worse if efficient broadcasts are impossible, e.g., due to some point-to-point links or if authentication is required and asymmetric signatures cannot be considered. Thus, this article introduces Scalable Multipath Exploration in Ad-Hoc Networks (SMEAN) as a method to discover, estimate, and select ad-hoc multipaths. SMEAN uses an overlay structure that is embedded into the transport network to discover overlay paths that utilize highly disjoint underlay paths. The low overhead allows for a reactive usage, e.g., when a VoIP is established. A simulative evaluation shows that SMEAN is able to set up suited multipath topologies with only a fraction of the messages needed by common ad-hoc routing algorithms.