Towards Efficient Message Dissemination in Cognitive Radio Ad Hoc Network

This article studies the problem of message dissemination in Cognitive Radio Ad Hoc (CRAHNs) over TV white bands. By exploiting the supreme propagation characteristics of low-frequency channels, this article proposes two message dissemination protocols that use acknowledged transmissions to guarantee dissemination reliability. These two protocols rely on assistance from neighboring terminals to expedite the dissemination process. However, the first of these protocols suffers from an excessive number of collisions due to the numerous concurrent transmissions on very few channels. To overcome this, a third protocol is proposed wherein assistance is renounced. Computer simulations show that the third protocol has the best performance. It also shows that concurrent transmissions have deep impact on the performance of the first protocol.