Resilient Caching in Information-Centric Networking

Information-centric networking (ICN), a new network architecture for efficiently delivering content, has been widely investigated recently. To be widely spread as a social infrastructure, ICN is required to sustain not only network availability, i.e., connectivity between operating routers, but also content availability, i.e., reachability to content, at network failures. In ICN, FIBs (forwarding information bases) at routers are configured so that content requests reach hosts of content providers having the originals of content. Therefore, requests for content whose connectivity to originals is lost cannot be transferred in networks, and the content availability of these content items is lost. However, copies of unavailable content are possibly cached at one or more operating routers in ICN, so content availability can be recovered by promoting one copy cached at operating routers to the original. Therefore, it is desirable to cache content at routers located far from its original to improve the recover probability of unavailable content items. In this paper, we propose a caching strategy of ICN to achieve this goal. Through numerical evaluation, we show that the proposed caching strategy can increase the maximum distance between the originals and cached copies by several percent to about 20% compared with the case simply caching content at all routers in ICN.