## Cryptology ePrint Archive: Report 2011/612

IBAKE: Identity-Based Authenticated Key Exchange Protocol

Vladimir Kolesnikov and Ganapathy S. Sundaram

Abstract: The past decade has witnessed a surge in exploration of cryptographic concepts based on pairings over Elliptic Curves. In particular, identity-based cryptographic protocols have received a lot of attention, motivated mainly by the desire to eliminate the need for large-scale public key infrastructure.

We follow this trend in this work, by introducing a new Identity-Based Authenticated Key Exchange (IBAKE) protocol, and providing its formal proof of security. IBAKE provides mutually-authenticated Key Exchange (AKE) using identities as public credentials.

One identity-based AKE subtlety that we address in this work is the resilience to the man-in-the-middle attacks by the Key Management Service. For efficiency, we employ two Elliptic Curves with differing properties. Specifically, we use a combination of a super-singular and non-super-singular curves, where the super-singular curve is used as an identity-based encryption wrapper'' to achieve mutual authentication, and the resulting session key is based on a Diffie-Hellman key exchange in the non-super-singular curve.

We provide a detailed proof of security of the resulting protocol with respect to (our own natural adaptation and simplification of) the AKE definitions of Kolesnikov and Rackoff.

Category / Keywords: cryptographic protocols / Identity-based Authenticated Key Exchange

Contact author: kolesnikov at research bell-labs com

Available format(s): PDF | BibTeX Citation

Short URL: ia.cr/2011/612

[ Cryptology ePrint archive ]