Design and Optimization of VoD schemes with Client Caching in Wireless Multicast Networks

TL;DR

This paper explores how client caching can enhance VoD multicast performance in wireless networks by proposing optimized schemes for reactive and proactive systems, considering various access patterns and bandwidth constraints.

Contribution

It introduces joint cache allocation and multicast delivery schemes tailored for reactive and proactive VoD systems with client caching, addressing multiple access patterns and optimizing resource use.

Findings

Proposed schemes reduce bandwidth consumption and waiting time.

Analytical results validated by simulations.

Insights for designing scalable VoD networks with client caching.

Abstract

Due to the explosive growth in multimedia traffic, the scalability of video-on-demand (VoD) services becomes increasingly important. By exploiting the potential cache ability at the client side, the performance of VoD multicast delivery can be improved through video segment pre-caching. In this paper, we address the performance limits of client caching enabled VoD schemes in wireless multicast networks with asynchronous requests. Both reactive and proactive systems are investigated. Specifically, for the reactive system where videos are transmitted on demand, we propose a joint cache allocation and multicast delivery scheme to minimize the average bandwidth consumption under the zero-delay constraint. For the proactive system where videos are periodically broadcasted, a joint design of the cache-bandwidth allocation algorithm and the delivery mechanism is developed to minimize the average waiting time under the total bandwidth constraint. In addition to the full access pattern where clients view videos in their entirety, we further consider the access patterns with random endpoints, fixed-size intervals and downloading demand, respectively. The impacts of different access patterns on the resource-allocation algorithm and the delivery mechanism are elaborated. Simulation results validate the accuracy of the analytical results and also provide useful insights in designing VoD networks with client caching.