AIR-CB21AG-E-k9 intermittent association to AP1220s

[marcbutler]

Hi All

I am hoping someone may be able to shed light on this issue for me.

I installed a Wireless network of 40 1220s for a client. At the time, the .11g standard was not available. So, we installed .11b and .11a in most of the APs. We performed coverage testing (they wanted a coveraged based system as opposed to a capacity-based system) on both .11a and .11b and found that there was coverage throughout the entire campus with .11b and minor blackspots around .11a. The customer was happy with this.

However, we have just supplied them with the AIR-CB21AG-E-K9 tri-band cardbus adapters (we have not supplied any .11g rado module upgrades for the AP as yet). Since that time, they have been complaining that whilst using the cards in either dual- or tri-mode, they have been having issues with roaming between overlapping cells when connecting to the .11a system, in that they will loose connectivity completely and start re-authenticating, which could take 5 mins, or perhaps not at all in some areas. The cards will not automatically trip down to use the .11b infrastructure which is known to be good at the same location. Yet, they have some dual-band cards and those seem to be fine in similar areas. Also, they have some AIR-CB21A-A-k9 cards, and they seem to work fine in most areas, in areas where the tri-band cards have problems.

The equipment that I have not mentioned that we have deployed is as follows:

AIR-Ap1220B-E-k9

AIR-RM20A-A-k9

Windows XP clients

LEAP and PEAP authentication in operation.

I hope that someone can shed some light on this, if this is a known issue with the cards, or that I might require a software upgrade (currently running VxWorks 12.02T1) to be able to support these cards (even though I am not running .11g).

Hope to hear from someone soon

Rgds

Marc

[rmiles]

I hear you. My solution for now has been to downgrade back to the b cards.

[jcosgrove]

I have been considering that but our point of care carts are laptops mounted on carts securely. To open the cart to change the card takes about 16 screws and we have over 150 carts. If I go that route I better be right.

[jcosgrove]

It seems like you are right on the 350 card. I spent some time testing side-by-side the the 350 vs. CB21AG with both limited to 802.11b scanning and the 350 runs very stable as you go AP to AP. Most of the time only missing 1 ping. With the CB21AB card there seems to be usually 2 missed pings with the card going off and getting lost or deciding to associate to farther off AP's. One thing about the CB21AG is the latency of the pings seem to be only about 1ms VS 2-3 on the 350 so it must be a fast card. Maybe because that it is a card bus adapter.

[dzuodar]

hi everyone!

interesting that i found this thread here! at the moment i'm facing the problem as described in a lot of posts here. sw versions we use: AP1200 with IOS 12.2(15)XR and ADU 1.1.0.10 these are the latest versions that i know about...

anybody has already any news about possible solutions? i have implemented WDS with Fast Secure Roaming this week, but this hasn't solved anything :(

cheers,

Dimitri

[jcosgrove]

There is supposed to be a new release somewhere in the next 3 weeks that should fix this. I am testing a pre-beta version and it seems to make this problem go away. This has nothing to do with A vs B/G scanning. It is scanning in general. The card just decides to stop talking at times and not associate with any AP. 2-3 mins later it might start talking.

[rmiles]

I too am using this beta client. 1.1.0.15 right? In my preliminary testing roaming seems to be working better. I never lost more than 2 successive pings when roaming. I saw no total loss of connectivity.

The date I was told for a general release was Sept 1.

[m-briody]

Has this new client been delayed? When is the expected release date?

[rmiles]

I have been testing a new beta driver that seems to be more stable as far as connectivity goes. I can now traverse our three floors and not lose more than 2 successive pings. I didn't experience any total loss of my ip address like before.

I have been told that a general release won't be available until Sept 1.

[jcosgrove]

That is where I am at with this. Beta driver is working good so far.

[dzuodar]

i'm also using the beta 1.1.0.15 now and it seems indeed that the wireless connection is more stable and less interruption occurs, i have also received the instructions for changing the following driver parameters:BBS Aging Interval (def. 120 sec) to 60 sec and Scan Valid Interval (def. 60 sec) to 30 sec...

cheers,

Dimitri

[rmiles]

The new ADU has been released. I am testing it now.

[pdotchon]

How are people getting on with the new driver?

Any problems?

[dzuodar]

hi! in my opinion the beta-driver did a better job than the new release... even when seated on my desk i loose connectivity about one time an hour and i don't have any explanation for this: signal quality varies most of the time between excellent and good so there is no reason to drop connectivity.

cheers

Dimitri