ANSI X9。42-2003（R2013），规定了使用Diffie-Hellman和MQV算法的对称密钥协商方案。它涵盖了基于离散对数问题的密钥协商方案的域参数生成、域参数验证、密钥对生成、公钥验证、共享秘密值计算、密钥推导和测试消息认证码计算的方法。这些方法可被不同的方用于建立一段公共共享秘密信息，例如加密密钥。共享秘密信息可与对称密钥算法一起使用，以提供金融信息的机密性、认证和数据完整性服务，或用作密钥- 使用其他ASC X9密钥管理协议加密密钥。

ANSI X9.42-2003 (R2013), specifies schemes for the agreement of symmetric keys using Diffie-Hellman and MQV algorithms. It covers methods of domain parameter generation, domain parameter validation, key pair generation, public key validation, shared secret value calculation, key derivation, and test message authentication code computation for discrete logarithm problem based key agreement schemes. These methods may be used by different parties to establish a piece of common shared secret information such as cryptographic keys. The shared secret information may be used with symmetrically-keyed algorithms to provide confidentiality, authentication, and data integrity services for financial information, or used as a key-encrypting key with other ASC X9 key management protocols.