MQV (Menezes-Qu-Vanstone) is an authenticated protocol for key agreement based on the Diffie-Hellman scheme. Like other authenticated Diffie-Hellman schemes, MQV provides protection against an active attacker. The protocol can be modified to work in an arbitrary finite group, and, in particular, elliptic curve groups, where it is known as elliptic curve MQV (ECMQV).
MQV is incorporated in the public-key standard IEEE P1363.
ECMQV has been dropped from the National Security Agency's Suite B set of cryptographic standards.
Both MQV and HMQV have weaknesses, that are fixed in the FHMQV protocol (see )
Alice has a key pair (A,a) with A her public key and a her private key and Bob has the key pair (B,b) with B his public key and b his private key.
|1||Alice generate a key pair (X,x) by generating randomly x and calculating X=xP with P a point on an elliptic curve.|
|2||Bob generate a key pair (Y,y) by the same way than Alice.|
|3||Now, Alice calculate Sa = x + Xa(mod n). and send X to Bob.|
|4||Bob calculate Sb = y + Xb(mod n)..|
|5||Alice calculate K = h * Sa(X + xL) and Bob calculate K = h * Sa(Y + yL) with xL and yL the first L bits of x and y where and where h is the cofactor (generally 4 for ECMQV)|
|6||The communication of secret K was successful|