The cognitive Radio paradigm has recently received considerable interest to address the so called ?spectrum scarcity? problem. In the USA, the Federal Communications Commission recently issued the regulatory for the use of cognitive radio in the TV white space spectrum. The primary objective is the design of cognitive devices able to combine the use of spectrum sensing and GEO-location information with the concept of the cognitive control channel to manage the cognitive devices. The recent standard ECMA-392 defines physical layer and medium access control protocols to enable a network managed in a fully distributed fashion. In this work, we pursue the design of an efficient medium access control protocol for the cognitive control channel to flexibly and reliability exchange messages inside the cognitive radio network. In particular, we explore how the cognitive devices can improve their knowledge of spectrum vacancies by means of sensing when the distributed beaconing defined by ECMA-392 is used. Our main contributions are the following: 1) we propose a proprietary medium access control protocol based on the Standard ECMA-392; 2) we model the behavior of the cognitive radio network by means of an innovative urn model approach, 3) we investigate the access to the frequency channels of the cognitive devices with and without spoofing attacks and 4) we investigate the ability of the cognitive devices to identify frequency holes accounting for perfect and imperfect spectrum sensing, as well as we study the network throughput.