Abstract: To reduce fetching cost from a remote source, it is natural to cache information near the users who may access the information later. However, with development of 5G ultra-dense cellular networks andmobile edge computing (MEC), a reasonable selection among edge servers for content delivery becomes a problem when the mobile edge obtaining sufficient replica servers. In order to minimize the total cost accounting for both caching and fetching process, we study the optimal resource allocation for the content replica servers’deployment. We decompose the total cost as the superposition of cost in several coverages. Particularly, we consider the criterion for determining the coverage of a replica server and formulate the coverage as a tradeoff between caching cost and fetching cost. According to the criterion, a coverage isolation (CI) algorithm is proposed to solve the deployment problem. The numerical results show that the proposed CI algorithm can reduce the cost and obtain a higher tolerance for different centrality indices.

Key words: content delivery network (CDN), MEC, replica server deployment, minimum cost, greedy algorithm