Roaming with Autonomous Access Points AP7522

[dot1x]

If we configure multiple autonomous access points with same SSID and Security settings, would roaming work between APs?

[Daniel_Mejia]

Hi Moin,

As Ondrej pointed out, seamless roaming/handover by definition requires a controller oriented centralized deployment.

You can roam between APs in autonomous mode, but note there will be a break in the connection. The MU will have to re authenticate/associate to the next AP when the MU considers it should move to a BSSID with a stronger signal.

[Ondrej_Lepa]

Moin,

this depends on security you are using. With an unprotected network it will be almost seamless form 802.11 wireless perspective, but switch forwarding data will have no idea where to send session traffic and it will eventually time out.

That is where centralized management takes place - it handles the forwarding based on roaming notifications. In shot - AP1 knows client is about to roam, broadcasts notification to other APs around and releases client's the MAC from its wired interface. New AP2, where client roams to, accepts the notification and sends out broadcast "I have this MAC now" so switches are able to seamlessly forward data. Anything buffered on AP1 is then forwarded to AP2 directly so you won't lose the session (firewall traversal)

I am not saying this is a disaster, but it will be highly inconvenient. In case you use RF Guns just to send barcode scans over i.e. HTTP (push) it will be fine. However, if you use telnet to send data, you'll see session timeouts + disconnections.

Regarding the channel selection - yes and no.

• YES - they will change the channel automatically based on ACS (automatic channel selection) feature

• NO - it wont be centrally driven and you will not achieve as good result as with Smart-RF

Regards,
Ondrej

[dot1x]

That's what my understanding is.
Even if the SSID and security is same on all autonomous APs, they would have to re-authenticate.
End users are RF Guns, any idea if they would get disconnection while roaming between autonomous APs?
Also, does autonomous APs change the channel automatically?

[Ondrej_Lepa]

Moin,

be careful about what you call "seamless roaming"...

As Jian mentioned above, APs must be in the same broadcast domain in order to send / receive migration data.
However, we tested this only in adopted mode (valid MINT links among all APs in domain).
Without MINT links you may end up with broken VoIP sessions, no 802.11r etc.

In other words - we cannot guarantee seamless roaming using APs wihout a centralized management (including virtual controller)

Regards,
Ondrej