User's Manual

Wireless Array
278 Configuring the Wireless Array
 “Roaming Assist” on page 342
See Also
IAP Statistics Summary
Understanding Fast Roaming
To maintain sessions for real-time data traffic, such as voice and video, users must
be able t
o maintain the same IP address through the entire session. With
traditional networks, if a user crosses VLAN or subnet boundaries (i.e., roaming
between domains), a new IP address must be obtained.
Mobile wireless users are likely to cross multiple roaming domains during a
single session (especially wireless users of VoIP phones). Layer 3 roaming allows
a user to maintain the same IP address through an entire real-time data session.
The user may be associated to any of the VLANs defined on the Array. The Layer
3 session is maintained by establishing a tunnel back to the originating Array. You
should decide whether or not to use Layer 3 roaming based on your wired
network design. Layer 3 roaming incurs extra overhead and may result in
additional traffic delays.
Fast Roaming is configured on two pages. To enable the fast roaming options that
you want to make available on your Array, see Step 28 to Step 30 in “Global
Settings (IAP)” on page 285. To choose which of the enabled options are used by
an SSID or Group, see “Procedure for Managing SSIDs” on page 254 (Step 13) or
“Procedure for Managing Groups” on page 272.