Cross-Layer Optimized Unicast and Multicast Routing on Overlay Networks

Abstract

Future military networks require capabilities beyond current commercial IP protocols for battlefield situations. These features include enhanced routing, network processing and information-centric networks. We developed a self-initiated and self-maintained overlay network (SIMON) to provide these capabilities. SIMONs aim at providing enhanced features using a methodology similar to IP-based virtual private networks. SIMON is comprised of a suite of protocols that constructs and configures overlay networks as well as routes packets in the virtual network. In this paper, we describe the overlay network routing protocol (ONRP) to provide efficient unicast and multicast routing in SIMONs. ONRP is specifically designed for an overlay network and exploits information available from SIMON and layer 3 routing protocol ONRP uses. In ONRP, each node in the SIMON independently tracks local virtual topology changes. The changes are efficiently distributed to the entire SIMON without the use of flooding, hence reducing ONRP's overhead. ONRP also uses very small update packets. For example, we show that the ONRP overhead is approximately 8 times less than OSPF in a dense 5 connected overlay network. The underlying structure of the topology distribution method is also used to route packets for multicast applications. The ONRP operations, however, are transparent to and independent of the underlying IP routing protocols. We have implemented ONRP on our wireless SIMON test bed. Most of the code runs in application space, with some small modifications to the forwarding engine in the Linux kernel