Question : Two Cisco 1200 APs - Trying to setup roaming configuration

Hi,

I have two Cisco 1200 APs setup on channels 1 and 6.  They both have three SSIDs setup on them (same on each unit) pointing to three different VLANs.  On my 104 VLAN, I have our data network and on our 105 VLAN our Cisco phone network.  The 104 VLAN is setup with WPA-PSK security (open auth) and the 105 VLAN is setup with WEP.  Both laptops and phones can connect to each AP and work on the network.

Here is my issue, if I walk from one end of the building to the other, I should be able to switch to the next AP seamlessly without dropping too many packets.  If I keep a constant ping active on my laptop and walk to the other AP it will switch but can't seem to get a DHCP address or network connectivity again.  It will eventually disconnect from the AP.  After about a minute the laptop will try again and connect to the new AP and the ping will resume.

Any thoughts?

Regards,
John

Answer : Two Cisco 1200 APs - Trying to setup roaming configuration

Long story short, most 802.11 networks have to break the connection from the old ap before then can connect to the new ap.
Give this a read:
http://www.ciscopress.com/articles/article.asp?p=102282&rl=1
But the outage time can be minimized.

Even in worse case, it should only take 1-2 seconds to switch to the new AP if you have properly implemented layer 2 roaming and providing the signal strength is there. If you walk until you see the pings fail. Stop walking. Does the new AP pick up while you are standing there? Is it's signal good? If so, then

It comes down to reducing the scanning, re-association and re-authentication times.
When signal is degraded to a set amount, the client starts scanning for a better ap, while keeping the link up to the degraded ap. You set this level on the client.
The client can pre-associate with the new AP and pre-authenticate (or possible have the authentication cached for up to 24 hours.).
So, when the signal on the new AP gets to a certain level over the degraded AP(or just dies entirely), the client switches to the new APs channel (possibly after sending a power saving message to the old AP, so the incoming packets will be catched.) and only has to go through the final 2 way authentication with the new AP.  

This link covers the ios upgrades and client software needed. Your cisco 1200 supports fast roaming, but your nic might not be supported. http://www.cisco.com/en/US/products/hw/wireless/ps430/prod_technical_reference09186a00801c5223.html#wp39046

I hope this helps,