One Time Password based Mutual Text Authentication

Many applications in the internet using Password for identify users.  So, this password must be strong and safe to avoid unauthorized users. The critical issue in many applications such as web-sites and data base systems is password authentication code (PAC). In this paper, PAC between two parties to confirm password authentication between them based mutual text authentication has presented. Two factors is the best solution in this field. But to be more secure and to be more efficient a legitimate user needs to make sure about his partner to ensure their communications should use another method without need more costs and avoid plurality of algorithms.  So, this solution uses mutual text authentication as new solution which the text is predetermined by users. This method is considered new in this field, as this method tries to make the password highly secure in front of unauthorized users and to make the process of accessing information specific only to the actual authorized users. When analysing this method, we find that it has many characteristics such as the confidentiality of the session key and privacy, in addition to the exchange of authentication between the two parties to ensure that others do not interfere.