Patent ID: 7373508
Filing Date: 2008-05-13
Classification: H04L,H04W

Abstract:
1. A method for reauthentication during client roaming in a wireless network system, the network having at least one access server operable to communicate with an a remote authentication server during an initial authentication of the client, and a plurality of access points, the access points being registered with the access server, the method comprising: receiving a registration request at the access server from a new access point for a roaming client registered with the access server and previously in communication with an old access point, the request including a ticket or authenticator; authenticating the registration request with an authentication extension generated with a secret session key shared by the new access point and the access server, wherein authenticating the registration request comprises comparing timer values from the client and the new access point; and sending a client's session key from the access server to the new access point in a registration reply upon authentication of the registration request at the access server; wherein the client's session key is configured for use by the new access point to reauthenticate the client and establish encryption keys for the client without contacting the authentication server; and wherein said at least one access server comprises a central access server at a top level of a hierarchy, and a local access server at a second level of said hierarchy and registered with the central access server, the access points located at a third level of said hierarchy.