Authentication of Diffie-Hellman Protocol for Mobile Units Executing a Secure Device Pairing Procedure in Advance

Abstract

It is well known that all public key cryptosystems, including Diffie-Hellman key distribution protocol, are vulnerable to a man-in-the-middle attacks for which adversary manage to share the key with legitimate users. In order to protect protocol against such attack it is necessary to authenticate so called Diffie-Hellman values using some additional secret information shared by legitimate users in advance. For mobile units using for communications between portable devices it is very appropriate to extract such authenticating information executing secret device pairing process. But a drawback of such method is slightly disagreement between authenticating strings of different users. Mathematical model of such scenario is binary symmetric channel without memory. Authentication method based on the use of such additional strings corrupted slightly by errors and executing next the hash functions chosen from strongly universal2 hash function class is considered. The probabilities of the undetected deception and false alarm are proved. We proposed also methods of parameter optimization (the number of blocks and full authenticators length).

Keywords

• diffie-hellman protocol
• authentication
• universal class hash functuon
• wegman-carter algorithm
• the probability of the undetected deception
• the prodadility of the false alarm