Problem with WLAN connection

[dendude]

hi,

i seem to hav hit another problem......
my WLAN connection keeps switching from on and off.....
it says connected to the AP and then after a few seconds it says wireless connection unavailable...and then again it connects...

wat could be wrong??

i'm using Win XP with Intel Centrino processor on an IBM Thinkpad

Please help,

regards,

[M/Q]

Is the notebook the Centrino, with the onboard miniPCI wireless board? What is the other node you are trying to link up with. Was the connection working correctly at one time and it just seemed to start having this problem. You need to describe the situation in more detail, so that we can begin to determine what might be wrong with it.

[tripwire45]

I periodically get those messages on my Dell Windows XP Pro laptop. I'm using 802.11b Linksys PC cards and AP. The signal will generally be "excellent" or "very good" but occasionally will go to "no signal" for a few moments. It subsequently recovers. I thought I read somewhere that this was normal for wi fi networks but perhaps I'm mistaken.

[RiDDeyZZ]

<~~~~Not an expert

As far as I understand of this subject its just one more reason for me to hate XP...I have seen a helpful link posted in other similar threads.

http://www.math.uwaterloo.ca/mfcf/computing-environments/wireless/xp.html

[M/Q]

Your assessment is a very good one and should be looked at seriously. We have had a few threads talking about the evil WZC and its issues. Another interesting drop cause is the link below and I just found this as a possible cause today.

http://arstechnica.com/news/posts/1080251780.html

[dendude]

thanks guys.......that was of gr8 help....

if Win XP is so evil then i dont want it to measure WLAN signal strength for me ;)...... can someone send me or tell me if i could get a piece of code to measure signal strength somewhere.....
i guess there r WinAPI's to do that.....
i saw WRAPI somewhere on the net.......but that dint run properly...

Any help pls,

regards.
:(

[M/Q]

Well, I am going to take a chance here. I do not regard WinXP as bad or have ever really said that. XP is one of the best desktop operating systems out there. There are no real other choices that come close. If anyone feels that some of the older OS's are better I would suggest that they go back and use them for awhile. I would really hate to have to put all my clients back on Win98. One other point I want to make clear is that I am a RedHat certified tech, so I have some experience with the other OS's as well. XP has some shortcomings as any new product will have. They are trying new things and just do not get it right the first time. WZC happens to be one of the problem areas. That is what I was referring to.

As for a signal strength utility they all will be subjective as there is nothing to calibrate the utility to. All of them must be used in a relative manner. I can put NetStumbler on two different notebooks, same brand and model, same wireless pc card, but different firmeare and get different readings. If you are interested there are several utilities out there that will accomplish the strength measure ment. Here are a few links.

http://www.netstumbler.com/

http://www.wardriving.com/code.php

[dendude]

thanks mpkn3rd.....

those links were pretty useful but my main concern is still not solved......i.e disassociating from the Access Point (AP).....

while checking out on the net i came across this software called WRAPI at http://ramp.ucsd.edu/pawn/wrapi/ which has a function to Disassociate from an AP.

has anyone used this software.....if so can u tell me how i go about using it......
i seem to hav followed all the steps mentioned on the site correctly but there is'nt any output......

Pls help..

regards.

[M/Q]

Your original post is somewhat confusing now. Are you having trouble staying associated or are you having trouble staying dis-associated? It is not very clear whatr you are trying to do. If you are trying to stay disassociated, you will have to disable the Windows Zero Configuration:

Start>Run. Type services.msc and hit Enter.
Double click on Wireless Zero Configuration.
Change "Startup type:" to Manual.
Click on Stop button.
Click OK, then close out sevices window.

[dendude]

no....my main problem now is not staying associated or dis-associated...
wat i wanna do is associate and dis-associate to an AP at will......

that is control my association with the AP.....this i hope to achieve programmatically.........
this is not related to my original post........

is my problem clear now??

regards

[M/Q]

Then you would have to turn off the Windows Zero Configuration like I mentioned in my previous post as that is what it tries to do many times a second.

[dendude]

but if i turn off WZC then i would have to re-boot the system in order for the changes to take place....
wat do i do then?

dendude:)

[M/Q]

Once you have the service on manual, it will not restart unless you enable it your self. That would be an initial setup, I guess.

[dendude]

i just tried starting and stopping WZC but i still stay connected to the AP........
the WZ service is set to manual..........

[M/Q]

If I understand it correctly you will stay connected until you shut the link down. What shutting WZC off does for you is prevent it from finding and linking to open nodes when you do not want to.

[dendude]

that is exactly wat i dont wanna do......
wat i wanna do is connect and disconnect from WLAN.
suppose i hav a button in my application, on clicking it i want to connect to WLAN and on clicking it again i should disconnect.
Pls dont tell me to disable and enable the adapter bcos
when i disconnect i should still be able to measure signal strength

i'm open to registry handling.......

Pls help,

thanks & regards,
dendude.

[M/Q]

I see that we are not listening to each other.

First it is my understanding that there are two places where the association between nodes occurs. One is in Windows XP. It uses the WZC to connect to the node with the best signal condition. It gives you no choice. That will have to be disabled as mentioned before or it will continue to try and seek out the best signal source.

Second the generic wireless client firmware is developed to use two different approaches. First if it hears beacon management frames it will remain passive and try to associate with the best signal source that way. If there are no beacon management frames the client will send out active request frames trying to elicit a response from an AP style node.

I told you this before in the other similar thread we had about this subject. IMHO you have to disable these two processes in order to achieve what you want. I told you in my limited experience that you would need to develop a new driver for the wireless pc card in order to control that process. I suggested using Linux and compiling a new driver that way. The other obvious thing is to disable the WZC so it has no ability to overrule the shut down command.

Then if you want to be able to obtain signal strength information you will have to be able to put the pc card in promiscuous mode at will as well, or use the same approach as that used by NetSumbler and throw out active requests.