The cryptography used in the IoT today comprises the same cryptographic trust mechanisms used in the broader Internet. Like the Internet, however, the IoT is scaling to unprecedented levels that require far more distributed and decentralized trust mechanisms. Indeed, many of the large-scale, secure IoT transactions of the future will not be made of just simple client-server or point-to-multipoint cryptographic transactions. New or adapted cryptographic protocols must be developed and added to provide scalable, distributed trust. While it is difficult to predict what types of new protocols will ultimately be adopted, the distributed trust protocols developed for today's Internet applications may provide a glimpse into where things may be going with the IoT.
One such protocol is that of blockchain, a decentralized cryptographic trust mechanism that underlies the Bitcoin digital currency and provides a decentralized ledger of all legitimate transactions...