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New Member

CB21AG client ping delay periodicaly

We are using CB21AG(ADU3.0) and AP1131AG. The problem is ping delay happen periodicaly,ping destination is gateway and WLAN client to AP IP address. There is no radio interfernce and clean RF circumstance.

We have four CB21AG having same issue but intel centrino's ping response is clean. I've tried up and downgrading CB21AG divers and utilities, but same result.


Re: CB21AG client ping delay periodicaly


Some more information is needed here. are you in a production network environment, where there is other RF activity? You say there is no RF interference...does that mean you are in a test environment with one AP and one client?

How bad is the ping delay? Usually the ping delay between the client and the AP is 1 - 2 ms, since this is just the radio link. If this is where you are experiencing the delay, you need to look for same channel co-located AP's, Microwave ovens, 2.4GHz cordless phones etc...

If this part is acceptable and the delay comes between the client and the gateway, specifically, then your problem most likely is on the wired side. Your wireless subnet should be on a separate subnet from the rest of your network.

Please make note of the times of day these anomolies occur. Lunchtime around the breakroom can be a little spastic on your wireless because of the microwave oven. You should endeavour to keep AP's off of channel 11 (assuming you are using only 1,6, and 11)near microwaves as this channel takes the most significant hit with a running microwave.

Find as much info as you can and report back...

New Member

Re: CB21AG client ping delay periodicaly

Did you ever find an answer to this. We are experiencing similar issues. We also experience periodic ping delays. I have tried the 3.0 and 3.5 firmware. We also use LEAP.

This ping delays were extremely bad(200-800ms) when we had A, B, and G enabled on the cards. If we limited the cards to just one speed the ping times were better, but not great. We also found that by removing the Cisco Wireless Utility and let Windows run the card, our ping times were consistantly at 1ms. Unfortunately, we cannot use LEAP with this method.

We brought in a consultant to investigate. He has seen this situation at other facilities. He says that the Cisco cards are junk and Intel are better. I have a hard time swallowing that and definately have a hard time paying for 200+ new wireless cards. If anyone else has suggestions please post.


Re: CB21AG client ping delay periodicaly

What a load of crap. Cisco cards are junk??

First, stop paying this idiot and send him home.

Second, from your post you are saying that when you use the windows software you are getting 1ms ping times. This is because you cannot use leap.

When you turn off wireless zero config and use the ACU ( without leap) are your ping times the same?

If they are (and they should be) then your consultant is on the Chronic and you just proved it.

This issue only happens when you use LEAP? Where (in hops) is the authenticating server? You need to figure out where the bad ping times start. What are the ping times from the laptop to the AP? To the Switch? To the router? etc.....

New Member

Re: CB21AG client ping delay periodicaly


We get the same ping times even when LEAP is disabled still using the Cisco client. We also have Aeronet 340 and 350 cards that do not experience poor ping time. These cards are using LEAP and connected to the same AP's as the ABG cards. This issue only occurs with our ABG cards.

I do like your idea of finding out where the ping delays start. Although, it is strange that a the 350 card works find and the ABG card does not and they are both connected to the same AP.

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