Local routing strategy for scale-free networks based on degree-load joint preference

A local, adaptive routing strategy for scale-free networks is proposed. The probability of a node to transmit packets to its neighbors is adaptively adjusted based on the relationship between the neighbors' traffic load and sending capacity. The probability is proportional to the α-th power of node degree, where α is a preferential factor that increases when the load is smaller than the capacity, and decreases otherwise. In this way, under small traffic load, packets can be priority forwarded to the nodes with large degree in order to reach destinations faster; under heavy traffic, decentralization of traffic load could avoid congestion in nodes with large degree, and make sure the forwarding capability of all nodes including large-degree and small-degree ones be fully utilized. So that the network can bear more traffic load. Simulations show that our routing strategy enhances network capacity and achieves lower average delay.