Age of Information in UAV Aided Wireless Sensor Networks Relying on Blockchain

Abstract

Nowadays, the freshness of status update data is critical for emergent tasks in wireless sensor networks (WSNs). This paper analyzes the peak age of information (PAoI) in the transaction-confirmation process of blockchain technology in the context of unmanned aerial vehicle (UAV) aided wireless sensor networks. Each access node transmits the latest packets to the associated access node, which processes the packets relying on blockchain technology. We investigate the transaction-confirmation process based on a finite-buffer batch-service <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${\bf GI/M^{[b]}/1/N}$</tex-math></inline-formula> queueing system. Additionally, the embedded Markov chain techniques are utilized to obtain the state probabilities of the system. Moreover, we deduce the closed-form expressions of average PAoI, which regards as the worse case of the update packet's freshness. Numerical results verify that reducing the block size and the queue length leads to a lower PAoI. Besides, fixed interval network traffic and Markov property network traffic based situations display much better aging behavior than other situations.