wireless lan and roaming

[sarahr202]

Hi every body!

i have few question about roaming in wireless lan. All access points are autonomous in my example.

case#1

roaming within subnet:

two ap(ap1 and ap2) with overlapping each other cell but differerent sids.ap1 has ssid abc,while ap2 has ssid def.

Both are configured for roaming.

Can user roam into ap2 cell from ap1 cell?

simply put,Is it necessary for aps to have same ssids for roaming?

case#2

roaming across different subnets:

suppose we have router with two fast ethernet interfaces.

f0/1 is connected to ap1

f0/1 ip address 199.199.199.1 255.255.255.0

f0/2 is connected to ap2

f0/2 ip address 198.198.198.2 255.255.255.0

Is there any way besides mobile ip to support roaming between ap1 and ap2?

[Istvan_Rabai · Accepted solution]

Hi Sarah,

Case#1

For roaming the SSIDs must be the same on both APs.

The AP where the SSID matches the client configured SSID will accept the association request from the client.

Case#2

For roaming between subnets (layer3 roaming) you will need at least one Wireless LAN Controller (WLC) and APs with Lighweight software image, so they become Lightweight APs (LAPs).

LAPs can connect to the same WLC and service different client subnets.

If the LAPs connect to different WLCs then the WLCs will use the mobility exchange feature to support roaming using the so called "Ether-IP" tunnel between them.

Cheers:

Istvan