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Hello all,

I use Cisco wireless hardware in our WLAN, we have about 50 users on two floors, the bulk of the users are spaced around on the second floor.

Previously I used G series Cisco 1130AG access points and 802.11 abg client adapters. Recently I upgraded to Cisco 1141 N access points and Cisco/Linksys wmp600n client adapters. All clients are running desktop computers.

No site survey was done for the new upgrade, but was done previously for the previous generation hardware. I put the new access points in the same physical location's as the G series access points were. There is a total of eight access points in the office, six on the second floor, two on the first floor.

Now I have two access points on the second floor that do not cooperate, clients that are closest to those AP's do connect, however after a few hours they disconnect and connect to another AP that is the next closest to them. their connectivity does not suffer, whether they connect to the closest AP, or the next closest which is about 50 - 60 feet away they still have an excellent signal strength and their speed is 130MB.

I checked/re-checked configurations and all AP's are the same. I even increased the client power on those two problem AP's at a higher power to see if I can keep clients on, but no good. All access points are using static non-overlapping channels - 1,6,11 - each AP has a different channel and they are not close to each other when a channel is repeated.

Now when I had my former G series AP's in the same location as the two that are not cooperating - the G series AP's always had clients connected, and they were connected all day. Once I replaced the G with the N in the same two physical locations, the N is not holding clients like the G series did in the same physical location.

Can someone shed some light on this to let me know why clients that are close to these two AP's do not stay connected, they go to the next closest AP's, but clients did connect when I had the G series in place. I also spoke to Cisco support, and unfortunately no luck.

Thanks,
Bob

Well, didn't you say you changed the adapters as well?
If they are just roaming away then its the client that makes that decision. You might check the roam aggressiveness or roam tenancies (driver options vary) on the cards.

Rather than increasing the power on the close APs you may want to see if you can decrease the power on the other near by APs. Make sure you don't create coverage holes.

If the client is not just roaming away then Cisco will have to answer that but ill bet its just a client roaming issue and not cisco's fault. (as much as i would like it to be :).

-steve

Curious if those two APs are in the same part of the building or on different sides of the building. Are those two APs on the same or different channels?

Were your old 1130s dual band? You could get them with a 2.4GHz radio only.
What were your old clients using for a wireless card?
IOS or Controller based? I am guessing IOS.
What is the problem if they roam?
I am guessing you are getting complaints about slow performance?

As Steve hinted clients choose to roam, not really up to the AP. You can go in to device manager and then in to the advance options of the wireless NIC and adjust some of these settings.

In MOST cases this true. You are however dealing with Cisco products. This means you have Cisco's aironet extensions (CCX). With CCX you can control roaming behaviors of clients. It even allows you to load balance clients between APs. I'd guess the Cisco/Linksys adapter supports CCX. You should be able to see the if CCX is supported on the AP'swebpage for the client, it should also tell you the version it supports. http://www.cisco.com/web/partners/pr46/pr147/program_additional_information_new_release_features.html

Since I am guessing your getting performance complaints. I have some suggestions for you. Get off of 2.4GHz! You have dual band APs and clients. I'd set up a 5GHz only SSID or even set the advance Wireless NIC settings to use 5GHz only. Since they aren't mobile like a laptop I'd static some of the advance settings on the clients if needed. I'd also bond the 5GHz channels to 40MHz wide. On 5GHz I'd guess you won't have any old A clients. Where on 2.4 you'll have probably have a G client and hopefully not a B client. So on 5GHz you can get greenfield mode N. I'd disable slower data rates also.

http://www.cisco.com/en/US/solutions/collateral/ns340/ns394/ns348/ns767/farpointWLAN_strategies_wp.pdf

never mind the last part... 1141 doesn't have a 5GHz radio.

As stated by others, I would suspect that this is a Client, rather than an AP problem.

However, as you said, you did not do a new Site survey for the "n" network. This is counter to most suggestions I have seen. This might be one of your problems.

I suggest you do a new survey as you have the AP's installed now.

Hello all,

Thank you for the replies.

I did not see any settings in the Cisco/Linksys wmp600N client adapter for roaming or CCX on the adapter. So I called Cisco adapter support and no help there, they said the adapter relies on the AP settings ----- and nothing to set/change on the adapters. Which is different that the Cisco AP group told me and the same as here ---- the client makes the decision....

Concerning some earlier questions -----

I used the same settings that was set on the G series AP's as the N AP's - example - on G series, Accounting AP was on channel 1, 50W client. I set the N series for Accounting to be on channel 1 and 50W client power, followed the same pattern on all replacement AP's.

The AP's are spaced apart throughout the office, when the channels are repeated the next AP is on the other side of the building. I have 6 AP's on the second floor, they are set --- 1,6,11, on one side of the office then 1,6,11 on the other side of the office, not close to each other at all. The two that are not cooperating are on different channels, one is 1 the other at the other end of the building is channel 6.

Problem for doing a survey is I do not have a notebook handy, but a Mac which is my personal notebook. I did find software called netspotapp for the Mac ---- I want to install/try that on my Macbook Pro, to see if I can get a decent site survey around the office. I will also lower the client power one notch on the closest AP's to see if that will help the two that are not cooperating.

Thanks,
Bob

Can we start blaming Cisco yet?

-Steve <-- Biased :)

I love it. Asked 5 questions not one answer in the reply.

http://www.intel.com/support/wireless/wlan/sb/cs-025393.htm

Franman, I don't understand your comment. Do you expect an answer based upon what some people might consider to be incomplete information?

BP expressed thanks for the various responses, several of which contained suggestions.

If only explicit and correct reponses were made to every question on this site, there would be a much larger number of posts which never receive an answer of any kind.