Common Contracts

A New Authentication Mechanism and Key Agreement Protocol for SIP Using Identity-based Cryptography

April 10th, 2006

• Filed
  April 10th, 2006

The Session Initiation Protocol (SIP) protocol is commonly used to establish Voice over IP (VoIP) calls. IETF SIP standards do not specify a secure authen- tication process thus allowing malicious parties to impersonate other parties or to charge calls to other parties. This paper proposes an extension to the SIP protocol that uses an identity-based authentication mechanism and key agreement protocol. These extensions provide stronger cryptographic assurances for VoIP authentica- tion and enable provably secure key agreement between users. The use of ID based cryptography means that a large Public Key Infrastructure (PKI) is not required thus making this protocol viable for large scale implementation.