A hierarchical identity-based security for delay tolerant networks using lattice-based cryptography

Routing and secure communication are important concerns in Delay Tolerant Networks (DTNs). Previously designed security schemes utilize traditional public key cryptosystems for entity and data security that provide security under some hard problems like integer factorization and discrete logarithmic problems. These algorithms are vulnerable to Quantum attacks. In this paper lattice based cryptosystem has been used first time for DTN security. Lattice based cryptosystems utilize post-quantum cryptographic algorithms which are unbreakable by quantum attacks. First we present a novel Hierarchical structure for DTN having intracluster and intercluster communications. Then, we propose a security design to provide end-to-end security to DTN application data using lattice based cryptographic signature and encryption algorithms, secure under LWE hard problem over lattices. For securing intracluster and intercluster communication, three new schemes have been proposed: (i) Lattice based hierarchical identity-based key agreement scheme, based on lattice based Diffie-Hellman key agreement protocol, secure under LWE assumption but adapted to hierarchical structure. (ii) To derive new session keys, i.e. keys for new joining nodes and for key refreshment, a new lattice based hierarchical identity-based key update scheme has been proposed, which is based on Singh et al.’s lattice based forward secure identity-based encryption algorithm, (iii) A lattice based non-interactive key agreement scheme, based on schemes proposed by Agrawal et al. and Singh et al., has been proposed for generating a secret key for two communicating nodes in different clusters. This design can effectively resist man-in-the-middle attack, replay attack, dictionary attack, and parallel session attack and maintains forward and backward secrecy.