A Multi-Class Blockchain Services Framework for Communication Networks

Blockchain-based applications have been recently introduced in communication networks. Different applications require different levels of service whereas existing blockchain-based applications mostly provide a single class of service. In this paper, we propose a multi-class blockchain services (MCBS) framework that prioritizes the processing of time-critical blockchain-based applications in communication networks. We model MCBS as a queueing system and derive the average service times for the different classes. We then formulate a multi-objective optimization problem to simultaneously optimize the average service time and aggregate transactions arrival rate. The numerical results show that existing blockchains may not satisfy the requirements of time-critical applications whereas a high priority queue in MCBS may meet the requirement. In addition, we analyze MCBS under double-spend attacks and show that with maximum attacker hash power, the blockchain system can still be stable if the aggregate transaction arrival rate is lower than half of its maximum achievable value.