Identity federation technology has been widely used in recent years. But the solution for federate access is totally different between the Web-Based and Non-Web-Based scenarios. Furthermore, it is highly limited for lack of support from Non-Web-Based scenarios now. This paper proposes a generic federate access solution based on LDAP roaming, which can provide reliable identity roaming in any internet service. To service providers, our solution is transparent and looks like a LDAP. The paper first presents the difficulties in realizing LDAP roaming and discusses offers solutions to the implementation of LDAP roaming. Then it evaluates the easy integration and usability of LDAP roaming. Finally it compares the Generic Solution with the existing federal access solution.