Preventing Traffic Explosion and Achieving Source Unobservability in Multi-hop Wireless Networks using Network Coding

Privacy threat is a very serious issue in multi-hop wireless networks (MWNs) since open wireless channels are vulnerable to malicious attacks. Source unobservability is an attractive and desirable security property for many privacy-sensitive applications, and dummy messages are most commonly used to achieve this property. However, dummy messages may incur severe performance degradation or even service denial due to the explosion of network traffic. In this paper, we propose a novel scheme, called SUNC (Source Unobservability by Network Coding), to prevent traffic explosion while achieving source unobservability. With SUNC, specially designed dummy messages can be absorbed at intermediate nodes, and, thus, traffic explosion can be naturally prevented. In addition, SUNC can offer forwarder blindness, which is an important privacy property for thwarting internal attackers. Security analysis and performance evaluation demonstrate the efficacy and efficiency of the proposed SUNC.