In-band Bootstrapping in Database-driven Multi-hop Cognitive Radio Networks

Obtaining spectrum information efficiently is key to cognitive radio networks (CRNs). The database-driven approach has emerged recently as an alternative or supplement for spectrum sensing, and has been quickly adopted by the government and the industry. Within database-driven CRNs, master devices obtain spectrum information by direct connection to a spectrum database, while slave devices can only access spectrum information indirectly via masters. Out-of-band connections with a second network interface which do not depend on the primary spectrum channels can be used for the communication of spectrum information among masters and slaves. Alternatively, the in-band approach completely based on primary spectrum channels can be used, which eliminates the need for out-of-band connections and eases the adoption of the database-driven spectrum sharing. In this paper, we study the in-band bootstrapping process for database-driven multi-hop CRNs, where master/slave devices form a multi-hop networks and slaves need multi-hop communications to obtain spectrum information from the master during bootstrapping. We propose several protocols to reduce the bootstrapping time and protocol overhead. According to the analysis and simulation results, our proposed protocols can greatly improve the performance.