Blockchain-enabled spectrum access in cognitive radio networks

In this work, we propose a blockchain verification protocol as a method for enabling and securing spectrum sharing in cognitive radio networks. The spectrum-sharing mechanism is used as a medium access protocol for accessing wireless bandwidth among competing cognitive radios. We introduce a virtual currency, called 'Specoins', for payment to access spectrum. An auction mechanism based on a first-come-first-served queue is used, with the price for the spectrum advertised by each primary user in a decentralized fashion. The blockchain protocol facilitates the transactions between primary and secondary users, and is used to validate and save each user's virtual wallet. The blockchain also serves as a distributed database that is visible by all participating parties and any node can volunteer to update the blockchain. The volunteer nodes are called miners and they are awarded with Specoins. We propose diverse methods to exchange the Specoins in order to make leasing possible even by cognitive radios that are not miners. We show the improvement of the proposed algorithm compared to the conventional Aloha medium access protocol in terms of spectrum usage.