Nortel Networks 2300 manual Requirements for Roaming to Succeed, Active

Configuring and Managing Mobility Domain Roaming 187

Requirements for Roaming to Succeed

For roaming to take place, the roaming client must associate or reassociate with an AP in the Mobility Domain after leaving an existing session on a different AP in the Mobility Domain in one of the following states:

ACTIVE	The normal state for a client that has left radio range without sending a
	request to disassociate.
DEASSOCIATED	The state of a client that has sent an 802.11 disassociate message, but has
	not roamed or aged out yet.

In addition, the following conditions must exist for roaming to succeed:

•Mobility Domain communications must be stable.

Generally, the communications required for roaming are the same as those required for VLAN tunneling. A client can also roam among ports on a WSS when a Mobility Domain is inaccessible or not configured.

•Client authentication and authorization on the roamed-to AP must be successful on the first attempt.

If authentication or authorization fails, WSS Software clears the client session. Depending on when the failure occurs, roaming can be disqualified or delayed.

•The client must use the same authorization parameters for the roamed-to AP as for the roamed-from AP.

If the client changes its encryption type or VLAN name, WSS Software might record a new session rather than a roamed session.

Nortel WLAN Security Switch 2300 Series Configuration Guide