Dominating Set Theory Based Semantic Overlay Networks for Efficient Content Distribution

Overlay networks have emerged as a powerful and highly flexible method of delivering content. An overlay network is a network running on top of another network, usually the Internet. These networks are employed in many settings to provide logical communication infrastructure over an existing communication network. The main objective of the overlay network is to reduce routing path lengths, stretched by the overlay routing process. In most solutions developed, a kind of fixed infrastructure in the form of excessive message exchange is necessary to guarantee good overlay locality properties. This paper presents a richly connected overlay networks based on Dominating Set Theory to optimize the number of nodes for large data transfer. Fast Replica algorithm is applied to reduce the content transfer time for replicating the content within the semantic network. To download a file from different peers in parallel from the semantic overlay network (SON) a dynamic parallel access scheme is introduced where end users access the members of the SON at the same time, fetching different portions of that file from different peers and reassembling them locally. The load is dynamically shared among all the peers. An enhanced digital fountain with Tornado codes is applied to eliminate the need for retransmission requests from the end users. Receivers run the decoding algorithm to reconstruct the original content. In this no feedback mechanisms are needed to ensure reliable delivery. This paper analyzes the performance of sequential unicast and multiple unicast content distribution strategies and compares their performance with our scheme and also analyzes the impact of dominating set theory for the construction of semantic overlays