A digital certificate is the combination of a statement and a signature of the statement, signed by a trusted certification authority. This work proposes using generalized digital certificate (GDC), for user authentication and key agreement for efficient secure communication. A GDC contains user’s public information, such as the information of user’s digital driver’s license, digital birth certificate, etc., and a digital signature of public information signed by a trusted certificate authority(CA). In GDC, user does not have any public and private key pairs, therefore key management in using GDC is much simpler than public key digital certificate. The digital signature component of GDC is used as the secret token of each user that will never be exposed to any verifier. Instead, the owner proves to the verifier that he has the knowledge of the signature by correctly responding to the verifier’s challenge. The session key established using proposed approach can be used for secure communication between the entities.