Securing Mobile Phone Calls with Identity-Based Cryptography

In this paper, an identity-based key agreement system and its implementation for mobile telephony in GSM and UMTS networks is presented. The use of telephone numbers as public keys allows the system to piggyback much of the security overhead for key management to the existing GSM or UMTS infrastructure. The proposed approach offers solutions to the problems of multi-domain key generation, key distribution, multi-domain public parameter distribution and inter-domain key agreement. The feasibility of the approach is illustrated by presenting experimental results based on a Symbian implementation running on N95-1 and N82-1 Nokia smartphones.