Delay Oriented Content Placement and Request Redirection for Mobile-CDN

We consider a mobile-CDN system where base stations (BSs) are equipped with storage for replicating and distributing content. In such a system, BSs cooperation in replying user requests is a widely adopted mechanism. For such cooperative caching, a key issue is the joint optimization of content placement and request redirection, which has been intensively investigated in the literature. However, optimizing this problem to guarantee delay has not received enough attention. Practically, each BS maintains a transmission queue for replying requests issued from other BSs. We investigated the management of such transmission queues to guarantee the queuing delay. By solving an admission rate determination problem and a typical content placement and request redirection problem, the throughput of the system is optimized with no violation on the queuing delay. Finally, a real trace based evaluation demonstrates the benefits of managing transmission queues in improving the mobile-CDN system performance.