Short-Term Linkable Group Signatures with Categorized Batch Verification

In ad hoc wireless networks like Vehicular ad hoc Network (VANETs) or Wireless Sensor Networks (WSN), data confidentiality is usually a minor requirement contrary to data authenticity and integrity. Messages broadcasted from a node to other nodes should be authentic but also keep user’s privacy in plenty scenarios working with personal data. Group signatures (GS) are used to provide privacy and authenticity to the users. Moreover, GS with batch verification can be efficient. Nevertheless, the current solutions have practical drawbacks like using an expensive tamper-proof hardware, the computation bottlenecks of the verification and revocation phases, complicated certificate distribution/revocation or omitting important properties like short-term linkability which is demanded in several applications, e.g. change lanes of vehicles in VANETs. To our best knowledge, our solution employs the short group signature with short-term linkability and categorized batch verification for the first time. Our solution provides more efficient signing and verification than compared schemes. Moreover, the solution allows secure and practical registration and revocation of users. The usage of proposed scheme protects the honest users who can now join and securely communicate without losing their privacy.