ANSI X9.44;draft standard;standards;algorithm;Diffie-Hellman">
### Question 161. What are ANSI X9.42 and ANSI X9.44?

ANSI X9.42 [ANS94a] is a draft standard
for key agreement based on the Diffie-Hellman algorithm, and ANSI X9.44
[ANS94b] is a draft standard for key transport
based on the RSA algorithm. The former is intended to specify techniques
for deriving a shared secret key; techniques currently being considered
include basic Diffie-Hellman (see
Question 24), authenticated Diffie-Hellman (see
Question 25), and the MQV protocols [MQV95].
Some work to unify the various approaches is currently in progress. ANSI
X9.44 will specify techniques for transporting a secret key with the RSA
algorithm. It is currently based on IBM's Optimal Asymmetric Encryption
Padding, a "provably secure" padding technique related to work
by Bellare and Rogaway [BR94].

ANSI X9.42 was previously part of ANSI X9.30, and ANSI X9.44 was previously
part of ANSI X9.31 (See
Question 160).