6 Conclusion

Wireless ad-hoc networks are expected to grow larger and a routing protocol which scales accordingly is needed. Proactive protocols are most suited for this, because they have total information on the network topology. Hazy sighted link state is the most efficient in this class of protocols and therefore the most scalable.

Ad-hoc protocols are only scalable when the topology and connections between nodes are fairly static. In other cases, they flood the network and incur a delay on setting up a connection.

Hierarchical protocols are scalable, because they split a large network into smaller clusters. However, constructing clusters with the right properties and selecting a clusterhead in each clusters are problems which are not yet solved.

Geographical routing protocols are probably the most scalable. However, each node has to know its location, which may not be possible in all situations.

Which routing protocol to use depends on many properties: the reliability and bandwidth of the links between nodes, the stability of the network topology, whether there are popular nodes or connections are random. In most cases, however, HSLS is the most scalable routing protocol. In situations where a positioning system is already in place, a geographic routing protocol is probably the best solution.