Interest-Aware Joint Caching, Computing, and Communication Optimization for Mobile VR Delivery in MEC Networks

Abstract

In the upcoming B5G/6G era, virtual reality (VR) over wireless has become a typical application, which is an inevitable trend in the development of video. However, in immersive and interactive VR experiences, VR services typically exhibit high delay, while simultaneously posing challenges for the energy consumption of local devices. To address these issues, this paper aims to improve the performance of the VR service in the edge-terminal cooperative system. Specifically, we formulate a problem of joint caching, computing, and communication VR service policy, by optimizing the weighted sum of overall VR delivery delay and energy consumption of local devices. For the purpose of designing the optimal VR service policy, the optimization problem is decoupled into three independent subproblems to be solved separately. To enhance the caching efficiency within the network, a bidirectional encoder representations from transformers (Bert)-based user interest analysis method is first proposed to characterize the content requesting behavior accurately. On the basis of this, a service cost minimum-maximization problem is formulated with consideration of performance fairness among users. Thereafter, the joint caching and computing scheme is derived for each user with given allocation of communication resources while a bisection-based communication scheme is acquired with the given information on joint caching and computing policy. With alternative optimization, an optimal policy for joint caching, computing and communication based on user interest can be finally obtained. Simulation results are presented to demonstrate the superiority of the proposed user interest-aware caching scheme and the effective of the joint caching, computing and communication optimization policy with consideration of user fairness.