WAP200 roaming problem

[davidka]

Dear All!

Our customer ordered WAP200 APs and it seem that this APs have big problem with roaming. It seems that client changes the AP (the MAC address changing) but the network connection still broken. After 10-20 sec. the connection come back until the next roaming. (All AP have continous ethernet connection, unique channel, same SSID and WPA2 key)

Any idea?

Thanks

David

[Ramkumar Jayaseetharamar]

Hi David,

For roaming to occur in a appropriate way coverage area of APs need to overlap. For more information refer the link

http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps10047/ps10049/data_sheet_c78-501856.html.

Thanks,

Ramkumar.

[davidka]

Hi Ramkumar!

YES the AP coverage is overlapped! I implement WLANs years ago. As I wrote the client change the AP quickly (I saw that the connected AP MAC address is changing) but the continous network connection (e.g continous ping) goes dead. After every roaming event the client wait 30 -60 sec or more to get alive the connection to the server. I see other topics where the users has the same error with the WAP200.I hope Cisco can handle this failure of the AP and not scupper their customers.

Please tell me if you have useable idea,

regards

David

[David Hornstein]

Hi david,

the datasheet says I support the 802.11F spec on the WAP200.

According to my understanding, I cannot see how there can be absolute secure roaming without use of a radius server.

But needless to say below is a graph showing my PC jumping from one AP to another WAP200 and the delay (being the trough).

I cannot see a VOIP call surviving the observed delay.

I guess that's why we have a;

1. Better solution -  with the  the Access Point AP541  .

2. Best solution -  with traditional Cisco  Wireless LAN Controller and LWAPP.

I did try this a few times and did have faster failover, but i didn't investigate the delay, just report that there is an observed delay when jumping from one WAP to another .

My test consisted of  just transferring a large file to my PC  from my NAS unit.

I pulled the power on one WAP200 and the PC (lenovoT60) failed over to the other WAP200. I did not setup anything special with my wireless client.  Just a quick test using default wireless settings with only one SSID configured on my wireless client.

I cannot understand why you have a 20 to 30 second delay.

regards Dave

[ciscodreamweb]

I have the same issue. I did noticed that this has more to do with the wired switch beneath the access points. When we change it (different intelligent switch, non-managed switch, an old hub) this gap changes drastically both ways. I also noticed that use of VLAN's blocks the roaming to the point where it's unusable. I found that the best switching time is when I set AP speed to Mixed mode (802.11b/g). There is under 3 sec. ping gap. With "B-Only" mode (my clients are only 802.11b capable) roaming took sometimes over 30 sec. much longer when I was constantly trying to connect to the server - it took less time while not trying to connect - that's the opposite what I was hoping for. I suppose that this "network mode" maybe disabled some other extensions like 802.11F for example...

I wonder if you had any luck with your setup?

By the way:

I've noticed that only one antenna is working with that AP. How I did that: I have displaced one antenna using the extension cable to the point where the signal was weak. And it didn't helped to improve it. Then I've switched the connectors. Now I have signal far from the AP itself but not from the antenna attached directly to the box. I've tried with 3 devices (we have bought a lot of them - now I'm wondering why). Maybe I'm misreading the use of the second antenna? Is there another purpose for it? Anyway: this device is acting weird, in my opinion.

Regards

archie

[Eric Moyers]

Hi, My name is Eric Moyers. I am a Network Support Engineer in the Cisco Small Business Support Center.

For your main issue I would suggest calling into the Small Business Support Center and letting one of our Network Support Engineers help you with that issue. That number is 1-866-606-1866. We are open 24 hours a day 7 days a week.

For your question about the antennas, this device is considered 1X2.

Often times you will hear the term 2x2 or 1x2, or even 3x3. The first number represents the transmit streams that are used by that device, while the second number represents the number of receive streams that are being used. Basically, the more utilized Tx

and Rx paths, the greater the bandwidth. Asymmetric cases, such as a 1x2 antenna configuration provide more download speed rather than upload. It is also the reson that you see only one of the anteenas with a strong signal. THe weak one that you noticed is actually leed over from the antenna doing the broadcasting.

Hope this answers your question and we look forward to helping when you call the Support Center.

Eric Moyers
Cisco Network Support Engineer
1-866-606-1866

[ciscodreamweb]

Thank you Eric, that explains a lot. I would rather not call your Support Center from Poland it might get pretty expensive. Could I use email or skype instead? Could you provide it for me?

Is there a 2x2 or 3x3 device with transmit diversity (AP transmits on the antenna it receives. If transmission fails, the AP automatically switches antennas and retries). We would like to buy few of those if the roaming is so difficult to acquire.

Best regards

archie