Network layer connectivity awareness with application to investigate the OLSR protocol in tactical manets

We propose a new local networking metric, the network layer connectivity awareness (NLCA), to dynamically characterize the connectivity status at the network layer of mobile ad hoc networks (MANETs). The NLCA is a local view of routable destinations provided by a designated routing protocol, which may differ from the real-time physical layer connectivity (PHYCON), defined as destinations that can be reached by local nodes via (multi-hop) radio links. Such discrepancy can cause packet delivery failure because a route may no longer be available at physical layer. We present a simulation method to obtain the real-time PHYCON using the breadth-first search algorithm. We apply the NCLA metric to the optimized link state routing (OLSR) protocol in scenarios simulating tactical MANETs, and compare the resulting NLCA with the underlying PHYCON, illustrating the two measurements vary and differ under mobility. The proposed NLCA and investigation technique provide a method for routing performance analysis.