This document describes version 2 of the Optimized Link State Routing
(OLSRv2) protocol for mobile ad hoc networks. The protocol embodies
an optimization of the classical link state algorithm tailored to the
requirements of a mobile wireless LAN.
The key optimization of OLSRv2 is that of multipoint relays,
providing an efficient mechanism for network-wide broadcast of link-
state information (i.e. reducing the cost of performing a network-
wide link-state broadcast). A secondary optimization is that OLSRv2
employs partial link-state information: each node maintains
information about all destinations, but only a subset of links. This
allows that only select nodes diffuse link-state advertisements (i.e.
reduces the number of network-wide link-state broadcasts) and that
these advertisements contain only a subset of links (i.e. reduces the
size of each network-wide link-state broadcast). The partial link-
state information thus obtained still allows each OLSRv2 node to at
all times maintain optimal (in terms of number of hops) routes to all
destinations in the network.
OLSRv2 imposes minimum requirements to the network by not requiring
sequenced or reliable transmission of control traffic. Furthermore,
the only interaction between OLSRv2 and the IP stack is routing table
OLSRv2 is particularly suitable for large and dense networks as the
technique of MPRs works well in this context.