Secure Comprehensive File Distribution Schemes for Network Coding Driven P2P Systems

The main objective of Content Delivery Networks (CDN) is to assist content to end-users with high availability and high performance. Emergence of network coding allows CDN's to achieve that goal where nodes in the network not only forward but also process the incoming independent information flows. Previously the security aspect of CDN's is handled using a homomorphic hash function that imposes huge resource overheads. Later a new hash function implemented using sparse random linear network coding scheme has the potential to thwart the content manipulation attacks faced in CDN's at a significantly less resource drain. To further improve efficiency of the security measures we propose to use the above scheme in combination with cooperation strategies. The probability of correcting the error at time t is equal to the probability that at time t (and not earlier) at least one infected node checked its content, discovered the corrupted packets, and informed the rest of the nodes in the network who would be initiating sharing operations for the same content thus bolstering the verification mechanism further. For an optimized network performance this comprehensive network coding scheme is much better than prior individual schemes. A practical implementation of the proposed system validates our claim.