Maintaining source privacy under eavesdropping and node compromise attacks

In a sensor network, an important problem is to provide privacy to the event detecting sensor node and integrity to the data gathered by the node. Compromised source privacy can inadvertently leak event location. Existing techniques use either random walk path or generate fake event packets to make it hard for the adversary to traceback to the source, since encryption alone may not help prevent a traffic analysis attack. In this work, without using the traditional overhead intensive methods, we present a scheme to hide source information using cryptographic techniques incurring lower overhead. The packet is modified en route by dynamically selected nodes to make it difficult for a malicious entity to traceback the packet to a source node and also prevent packet spoofing. This is important because the adversary model considers a super-local eavesdropper having the ability to compromise sensor nodes. We analyze the ability of our proposed scheme to withstand different attacks and demonstrate its efficiency in terms of overhead and functionality when compared to existing work.