3Com 3CRWX120695A WXR100, 3CRWXR10095A, WX4400 3CRWX440095A WX1200 manual Defining a Mobility Domain

Defining a Mobility Domain 61

„Mobility Domain communications are stable. Generally, the communications required for roaming are the same as those required for VLAN tunneling. Roaming between ports on a WX is possible even if the Mobility Domain is down.

„Authentication, authorization, and accounting (AAA) on the MAP to which the client roams is successful on the first attempt. An authentication or authorization failure clears the client session. Depending on when the failure occurs, roaming can be disqualified or delayed.

„The client uses the same authorization parameters for the new session as for the old session. For example, changing the Encryption-Type or VLAN-Name parameter might cause a new session to be recorded, rather than a roam within the same session.

A disassociated session has a grace period of 5 seconds in which the session history can be retrieved and forwarded. After 5 seconds, the session is cleared, and its accounting is stopped. You cannot configure the grace period.

If the client MAC address in a Mobility Domain is not found in 5 seconds, the session is considered new.

The 802.1X reauthentication timeout has little impact on roaming. If the timeout lapses, 802.1X processing is performed on the existing association. Accounting and roaming history are not affected if the reauthentication is successful, because the client is still associated with the same MAP. If reauthentication fails, the session is cleared, and it is not eligible for roaming. If the client associates to the same MAP, that is recorded as a new session.

Roaming creates the following effects:

„Remote Authentication Dial-In User Service (RADIUS) accounting is treated as a continuation of an existing session, rather than a new one.

„For tracked users, you can view roaming history in the Monitor tab. See “Using the Client Monitor View” on page 415.

„The old session is cleared from the WX, even if the client did not explicitly disassociate from the MAP and the 802.1X reauthentication interval has not lapsed.