Providing Video Services With Diversified Viewing Qualities: A Scalable Video Coding Based Caching and Transmission Approach

This paper proposes a novel video caching and transmission scheme in cache and full-duplex (FD) relay assisted wireless networks, where parts of the contents to be requested are stored in the local caches of relay nodes. To provide diversified viewing qualities to multimedia users, we combine scalable video coding (SVC) with edge caching in this work. With the aid of SVC, each video is encoded into multiple layers, including a base layer (BL) and multiple enhancement layers (ELs). The super layers, each of them containing one BL and several successive ELs, are cached and transmitted to users to bring diversified viewing experiences. Under the proposed caching and transmission policies, we conduct comprehensive performance analysis. By using the tool of stochastic geometry, we obtain the analytical expressions for successful transmission probabilities (STPs) in cache hit and miss cases. After obtaining STPs, the cache-aided data rate (CADR) is derived. Simulation results validate the derived STPs and demonstrate that the proposed SVC-based random caching scheme with FD relays has great potential to increase the data transmission rate.