Reseach On The Key Issues Of Routing And Caching Scheme In Information-centric Network

ICN is a clean-slate method proposed for resolving the mismatch between host-to-host communication model to information-centric service or application, in which the content acts as the first citizen replacing of end host. The three primitive in ICN are publish/subscribe paradigm, universal caching and information-oriented security model. The publish/subscribe system decouple s the subscriber and publisher in time and space. For the universal caching and publish/subscribe paradigm, the name-based routing scheme in ICN should be different from the routing policy for Internet. The design of caching scheme and routing scheme may decide whether the ICN should be deployed successfully. The focus of this paper is studying the ICN caching and routing policy, and proposing the optimization solution based on different sceneries.The main work of research were concluded on the following five aspects, name-based routing scheme under edge-core separation ICN network, model the ICN on optimal energy consumption, pre-fetch operation based cache scheme, profit-based cache scheme, and cache capacity management.1. Research on name-based routing scheme under edge-core separation ICN networkOn the edge-core speration ICN network, and the attribute-based name scheme is adopted, the HHR is presented for delivery of content object. A Chord-like routing architecture is applied for manageing the routing of core domain. However, the content routing in edge domain can be divided into LR, DLPC and RPR. The LR can be decided by edge domain according to its own policy, while a step-wise hierarchical routing structure is given for DLPC and RPR. The simulation result shows that, HHR can be quickly deployed, avoid the flooding of both content information and request, and can be applied for large-scale network.2. Research on modeling the ICN on optimal energy consumptionNowadays, energy consumption is one of hot-topics. ICN designers have to pay more attention to power saving. The energy consumption for ICN is modeled at first, which is a joint optimization problem for content routing and scheme deployment. The two-step heuristic algorithm is proposed: RSWC is used to arrange the traffic without considering the in-network caching, to get the initial solution,while RSC is a fine adjustment for deploying the traffic with caching, and to get the near optimal result.3. Research on pre-fetch operation based cache schemeThe prefetch operation is essentially supported for chunk-based communication in ICN. Combing the universal caching, two prefetch driven models are proposed, date-driven model and caching-driven model. For a content router, if the downstream interest receivedsatisfying one of the above models, the router should pre-fetch the following chunks which may be requested in a near future. Each router decides its own pre-fetch operation based the downstream request. The pre-fetch based cache scheme can short the user perceived delay through improving the hit ratio of cache routers.4. Research on profit-based cache schemeCache scheme for ICN should concern the expiration time of content objects.Under the different size and different valid time of contents, the profit-based cache scheme is exploited. Each node determines whether to store the arriving content only depends on the profit value, and the replaced content objects should be decided simultaneously.5. Research on cache capacity managementThe cache capacity management for routers in ISP access network is studied under the constraits of funds invested by ISP and link bandwidth. The goal is to minimize the total network delay. Two methods is proposed for deploying the cache capacity:iterative layer-by-layer heuristic algorithm, and fine grained cache capacity management. For both methods, the mathematic model is given firstly to describe the optimazition problem, and resolve the problem according its own properities.