Research On The Optimization Of Transmission Performance For Network Coding Enabled Named Data Networking

NDN naturally supports in-network caching and multipath forwarding,but it requires sophisticated coordination among consumers,publishers and intermediate routers to combine the two feathers and realize multisource content dissemination.Besides,caching information at the fine-grained chunk level of granularity makes it inefficient to utilize the off-path cached content.Network coding combines routing and encoding and it has recently been utilized to achieve efficient multisource content delivery in NDN.However,it is a challenge to simultaneously support network coding and request pipelining in NDN in a cost-effective way.And current research on NDN with built-in network coding leaves much room for exploiting off-path cached content and caching management about reducing the overhead.This thesis proposes NC-NDN,a network coding and request pipelining enabled named data networking architecture,and an efficient forwarding strategy and a cost-effective caching strategy under NC-NDN.Specifically,this thesis mainly includes the following content:1.An NC-NDN architecture supporting network coding and request pipelining: we propose NC-NDN to simplify the sophisticated coordination among network nodes.NC-NDN processes packets based on a rank-based matching and makes the decision on whether to forward pipelined Interests according to the proposed prediction mechanism to reduce the number of Interest packets.Our preliminary experimental studies suggest that NC-NDN drastically improves the performance of content delivery and reduces the overhead of content transmission as compared to the state of the art.2.An on-demand off-path cache exploration based multipath forwarding strategy for NCNDN: this strategy is the first forwarding strategy to explore the availability of off-path cached content under NDN with built-in network coding.Each network node explores nearby off-path caches on demand when consumers begin to request a generation of content and then maintains the reachability information at the generation level of granularity.Then each consumer can simultaneously retrieve diverse content segments from the original content publisher(s)and the explored capable off-path caches.Our experimental studies validate that this strategy improves the content delivery performance obviously as compared to that in the present NC-NDN without exploiting off-path caches.3.A demand and responsiveness-based caching strategy for NC-NDN: for the problem of caching redundancy and frequent caching replacement under NC-NDN,we propose a demand and responsiveness-based caching strategy to enable cost-effective caching for the encoded blocks.In this strategy,each node makes caching decision according to Cache Value which takes into account its dynamic demand on the encoded Data packets of the requested generation of content,its distance to the original content providers,and its potential responsiveness to the future requests for the same generation of content.It commits to cache encoded blocks at more valuable nodes along the transmission path to reduce the unnecessary caching replacement.Our experimental studies show that the proposed caching strategy offers high-performance content delivery and reduces the caching overhead as compared to the ondemand off-path cache exploration based multipath forwarding strategy which adopts the caching everything everywhere strategy.