Versatile Extensible Security System for Mobile Ad Hoc Networks

Mobile Ad hoc Network (MANET) is becoming more and more popular in scientific, government, and general applications, but security system for MANET is still at infant stage. Currently, there are not many security systems that provide extensive security coverage for MANET. Moreover, most of these security systems assume nodes have infinite computation power and energy; an assumption that is not true for many mobiles. Versatile and Extensible System (VESS) is a powerful and versatile general-purpose security suite that comprises of modified versions of existing encryption and authentication schemes. VESS uses a simple and network-efficient but still reliable authentication scheme. The security suite offers four levels of security adjustments base on different encryption strength. Each level is designed to suit different network needs (performance and/or security), and the security suite allows individual end-to-end pair-wise security level adjustments; a big advantage for highly heterogeneous network. This versatility and adjustability let each pair of talking nodes in the network can choose a security level that prioritize either performance or security, or nodes can also choose a level that carefully balance between security strength and network performance. Finally, the security suite, with its existing authentication and encryption systems, is a framework that allows easy future extension and modification

Fine-grained reputation-based routing in wireless ad hoc networks

Ad hoc networks are very helpful in situations when no fixed network infrastructure is available. They are especially important in emergency situations such as natural disasters and military conflicts. Most developed wireless ad hoc routing protocols are designed to discover and maintain an active path from source to destination with an assumption that every node is friendly and cooperative. However, it is possible that the participating nodes are selfish or malicious. A mechanism to evaluate reputation for each node is essential for the reliability and security of routing protocol in ad hoc networks. We propose a fine-grained reputation system for wireless ad hoc routing protocols based on constantly monitored and updated first and second-hand reputation information. The nodes in the network monitor their neighbors and obtain first-hand information based on the perceived behavior. Second-hand information is obtained by sharing first-hand information with nodes’ neighbors. Our system is able to distinguish between selfish and malicious nodes and take appropriate actions in either case. We employ the moving-window mechanism which enables us to assign more weight to more recent observations and adjust responsiveness of our reputation system to changes in nodes’ behavior. We show that our fine-grained reputation system is able to improve both reliability and security of an ad hoc network when compared to a reputation system that does not distinguish between selfish and malicious nodes