Efficient use of route requests for loop-free on-demand routing in ad hoc networks
We present a new instantaneous, loop-free on-demand routing protocol for ad-hoc networks, the Labeled Successor Routing (LSR)protocol, which identifies loop-free successors to a destination using route-request labels (RRL). Each route request (RREQ), used during the on-demand destination search process by flooding, is identified uniquely by a sequence number associated with the issuing source address. Route replies (RREP), traversing loop-free paths created by RREQs, carry the associated RRL that is stored by nodes along the created successor path to the destination. Without requiring an explicit mechanism for loop-freedom, such as per destination-sequence numbers or source-routing, LSR allow neighbors of a source to reply to RREQs, avoiding the destination being the only node capable of replying, which is the predominant case in the Adhoc On-demand Distance Vector(AODV)Routing Protocol, and a necessity in the stripped-down version, AODVJr. Simulations results in networks of 50 and 100 mobile nodes show that LSR performs comparably or better than the Dynamic Source Routing (DSR)protocol, AODV, and the Optimized Link State Routing (OLSR) protocol.
Rangarajan, H. and Garcia-Luna-Aceves, J. J. Efficient use of route requests for loop-free on-demand routing in ad hoc networks. IFIP Networking 2005 Conference; 2005 May 2-6; Waterloo, Ontario, Canada.