A multi-metric routing protocol with service differentiation for cognitive radio ad-hoc networks

In Cognitive Radio Networks, secondary users are affected by the the activity of primary users on licensed channels. To solve this problem, most routing protocols select the most stable links/channels, or use the minimum delay route and switch to other channels when primary users become active. However, these approaches may lead to competition between the secondary users on the most preferred links/channels which may cause congestion and affect the quality of the transmissions. In this paper, a multi-metric routing protocol with service differentiation is proposed. The main idea is to use different routing metrics for different traffic types to select routes that satisfy the specific requirements of each traffic type and to make load balancing across the network. Simulation results show that, compared to other related approaches, our protocol provides better end-to-end delay and increases the aggregate throughput. It also achieves load balancing across the network.