—The two-server model is quite promising for password based authentication, well suited for the setting of federated enterprises. However, none of the existing two-server password based authentication schemes enables a user to use the same password over multiple service servers, which is deemed an important feature of the two-server model. In this paper, we propose a new scheme, enabling this prominent functionality. Our proposed scheme is password-only, and slightly more efficient than the latest two-server password based authentication scheme. Keywords-password authentication; guessing attacks; twoserver model;