Practical distributed secret key generation for delay tolerant networks

Abstract

SUMMARYDelay tolerant networks (DTNs) are resource‐constrained dynamic networks where a continuous end‐to‐end connectivity is not always available. In such a challenging network, a fixed infrastructure may not be connected when a DTN is partitioned or the message delay in the network is large. Thus, the traditional public key infrastructure system and identity‐based encryption (IBE) system are not suitable for DTNs because they rely on centralized infrastructures and require multiple round‐trip interactions. To address this issue, we propose a distributed secret key generation system with self‐certified identity (SCI‐DKG) that does not require any private key generator and threshold cryptosystem. Initially, each node generates a private key and distributes an initial message including a self‐certified identity and secret sharings to members in a DTN. Receivers independently authenticate the identity and extracts some encryption parameters corresponding to the identity from this initial message. We prove that SCI‐DKG is chosen ciphertext secure in the standard model, and it can resist potential network attacks. Simulation results show that SCI‐DKG has smaller delay and higher successful ratio of secret key generation compared with IBE and hierarchical IBE systems implemented in a DTN. Copyright © 2012 John Wiley & Sons, Ltd.