Abstract or Summary:
Password-based authentication is the most widely used authentication scheme for granting access to user accounts on the Internet. Despite this, there exists no standard implementation of passwords by services. They have different password requirements as well as interfaces and procedures for login, password change, and password reset. This situation is very challenging for users and often leads to the choice of weak passwords and prevents security-conscious behavior. Furthermore, it prevents the development of applications that provide a fully-fledged assistance for users in securely generating and managing passwords. In this paper, we present a solution that bridges the gap between the different password implementations on the service-side and applications assisting users with their passwords on the client-side. First, we introduce the Password Policy Markup Language (PPML). It enables a uniformly specified Password Policy Description (PPD) for a services. A PPD describes the password requirements as well as password interfaces and procedures of a service and can be processed by applications. It enables applications to automatically (1) generate passwords in accordance with the password requirements of a service, (2) perform logins, (3) change passwords, and (4) reset passwords. Second, we present a prototypical password manager which uses PPDs and is capable of generating and completely managing passwords on behalf of users.