The number of services a typical mobile user accesses has grown and this forces the users to manage the multiple user names and passwords daily. The same situation is extended to the home network service environments. Recently, DHWG (digital home working group) suggests that the framework for compatible authentication and authorization mechanisms for user and devices should be set up. SAML (security assertion markup language) is an XML based single sign-on standard, which enables the exchange of authentication, authorization, and profile information between different entities including mobile and home devices. In this paper, we propose a single sign-on scheme in which a mobile user offers his credential information to the home network to obtain the user authentication and accesses an another domain using this authentication based on the SAML standard. In this scheme, a mobile device keeps a string token called an "artifact" which verifies that the mobile user has been authenticated once by the authentication authority in the system. Having an artifact in the mobile device, it can overcome the handicap of the low computing and memory capability in the mobile device.