Time-Efficient Layer-2 Auto-Configuration for Cognitive Radios

Cognitive radios CR have the ability to dynamically adapt to local spectrum availability. In a network comprised of CR-enabled devices, layerauto-configuration involves determining a common set of channels also referred to as the global channel set to facilitate communication among participating nodes. This is a unique challenge as nodes in the CR network are unaware of (a) their neighbors and (b) the channels on which they can communicate with a neighbor. In this paper, we propose a time-efficient distributed algorithm for layerauto-configuration for a CR network. Our algorithm finds the global channel set in timeslots, where is the maximum number of nodes deployed, is the maximum number of available channels for communication and is the diameter of the network. All nodes know and . We present a diameter-aware and a diameter-unaware version of the algorithm. For highly sparse networks such as a linear chain topology where , with and , the diameter-aware configuration protocol terminates within "! #%$'&)(+* ! and the diameter-unaware version terminates within % ,!%# $'&)(+* ! .