Lightweight Privacy-Preserving and Secure Communication Protocol for Hybrid Ad Hoc Wireless Networks

We propose lightweight protocol for securing communication and preserving users´ anonymity and location privacy in hybrid ad hoc networks. Symmetric-key-cryptography operations and payment system are used to secure route discovery and data transmission. To reduce the overhead, the payment can be secured without submitting or processing payment proofs (receipts). To preserve users´ anonymity with low overhead, we develop efficient pseudonym generation and trapdoor techniques that do not use the resource-consuming asymmetric-key cryptography. Pseudonyms do not require large storage area or frequently contacting a central unit for refilling. Our trapdoor technique uses only lightweight hashing operations. This is important because trapdoors may be processed by a large number of nodes. Developing low-overhead secure and privacy-preserving protocol is a real challenge due to the inherent contradictions: 1) securing the protocol requires each node to use one authenticated identity, but a permanent identity should not be used for privacy preservation; and 2) the low overhead requirement contradicts with the large overhead usually needed for preserving privacy and securing the communication. Our analysis and simulation results demonstrate that our protocol can preserve privacy and secure the communication with low overhead.