Peer-Assisted Streaming Distribution over CCN

Abstract

CCN (Content Centric Networking) is a new network architecture, which is optimized for content distribution by introducing route cache and request aggregation. However, current CCN is still similar to traditional Client/Server network architecture, with limited cache space, and the request aggregation policy is suitable for live streaming media rather than streaming media on demand. The main reason is that user requests for streaming media on demand usually exist time difference, which may weaken the superiority of request aggregation policy and decrease the hit ratio of route cache, resulting that a large number of repeated requests are sent out by routing nodes. Some solutions focus on increasing the use ratio and hit ratio of route cache. However, those solutions exist some defects, such as with too high computational cost, not considering the real-time requirements of streaming service and the features of user requests. Aimed at the defects, we propose a peer-assisted streaming distribution mechanism over CCN, referred as PAS over CCN. In which, CCN user nodes are enhanced to support caching partial media resource, and new generated user requests are as far as possible forwarded to local CCN user nodes. Simulation results show that, PAS scheme can effectively reduce redundant network traffic, save bandwidth of egress routers, decrease the delay and hops for forwarding packets, and lighten the load of streaming media server.