Capacity Assurance in Hostile Networks

Linear network coding provides a new communication diagram to significantly increase the network capacity by allowing the relay nodes to encode the incoming messages. However, this communication diagram is fragile to communication errors and pollution attacks. How to combat errors while maintaining the network efficiency is a challenging research problem. In this dissertation, we study how to combat the attacks in both fixed network coding and random network coding. For fixed network coding, we provide a novel methodology to characterize linear network coding through error control coding. We propose to map each linear network coding to an error control coding. Under this mapping, these two codes are essentially identical in algebraic aspects. This methodology provides a new approach to understand network coding scheme. Meanwhile, we propose a novel methodology to characterize a linear network coding through a series of cascaded linear error control codes, and to develop network coding schemes that can combat node compromising attacks. This representation enables us to determine the independent source of errors in the cascaded network level. It could lead to a successful decoding of the original message and locating of the malicious network nodes. We provide a comprehensive theoretical analysis on network coding in both unicast and multicast scenarios.