Wireless for 200 people

[tahequivoice]

How can  something be deployed using a WLC and LWAP to service up to 200 clients in a conference environment.  I would be in 2 or 3 conference rooms, not in a major hall, but in a downtown city office building.

The limit for ALB is 20 per AP, so 10 AP's would be needed minimum, but wouldnt that present an RF nightmare?

[blakekrone]

What are the clients going to be doing on the wireless? At Cisco Live you can see upwards of 200 clients per AP and it's usable if they are just looking for Internet/email.

Not knowing the size of the conference rooms, wall structures, etc it's hard to say how many APs would be needed, but I could imagine you could get away with 2 or 3 APs per room. I would look at the WLC-5508 and AIR-CAP3600 APs.

[tahequivoice]

They currently have 3 1130 AP's and a WLC 2106, and when they get a conference in, the speeds drop horribly with a lot of disconnects, and a LOT of complaints.   I already had TAC look into it and the response back was too many users per AP. One AP had 45 users on it, with clients reassociating constantly.

The Aggressive load balance is limited to 20 on the WLC, and Cisco recommends no more than 24 tops per AP.

We could add more AP's, but my concern would be saturation of the spectrum, which can be worse than what they have now.

How close can each AP be to one another before they interfere with the overall network?

[blakekrone]

I wouldn't be adding more 1131's, I would be replacing those! I've seen 45 - 50 per 1142 for example with little to no issues.

There is no magic number in terms of feet, it's all about signal propagation.

Aggressive load balancing isn't a good solution either to be honest, I think that causes more issues then it helps.

What version code are you running as well?

[tahequivoice]

I heard the same about ALB too being more of a headache than it's worth.  The WLC is running the latest, or near latest, 7.1.116 I believe. 

I don't want to guess with this one, they are complaining too much about it, although it has been in production for nearly 5 years now, and they just now are really starting to use it.

Pending confirmation, 6 3500 series to replace the existing 3 1131 AP's should give them a lot more bandwidth to play with.  I would also suggest moving up to at least a 2112 or 2500 series WLC so they can add more AP's as they now are limited to no more than 6.

Could the problem they have be related to the model AP being used?   Are there other AP models that are more designed for a convention center type deployment?

[blakekrone]

The newer APs will help that is for sure, especially as you move into the 802.11n market.

While the 2500 is a fine WLC, I would move towards a 5508 to handle the client load. If you think about it you have 200+ clients hitting a single 100mb switch port on the 2100 series. The 2500 series does increase this to a gig port, but you only have one. I would recommend a 5508 with LAG and at least 2 of the SFPs loaded.

Ideally for your environment the AP-3600 referenced earlier would be best as this is kind of the "high density" deployment AP going forward. The 3600 has all of the features of the 3500 and then introduces a 4x4:3 MIMO antenna.

See more here:

http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps11983/data_sheet_c78-686782.html

[dschlicht]

Blake's comment above is right on. You must be sure that each hop on the way to the destination isn't a bottleneck for that amount of users. 200 users on wifi simply browsing email/web/video, etc. can quickly and easily saturate the network/Internet access.

Sent from Cisco Technical Support iPad App

[blakekrone]

Also, I keep forgetting to ask. What data rates are enabled on the WLC?

[tahequivoice]

I believe they are all at default.

[blakekrone]

If you can, disable 1, 2, 5.5, 6, 9, and 11 on the 2.4GHz side, then disable 6, 9, and 12 on the 5GHz.

12Mbps should be mandatory then on 2.4 and 18Mbps should be mandatory on 5Ghz.

[George Stefanick]

Just a note based on Blakes comments about PHY rates. You should make sure your deisgn supports the higher rates at the edge of coverage. By disabling the lower rates you will pull in your coverage area. If you have clients that connect at say 11 in the far corner prior to the change will not be able to AFTER the change.

[Leo Laohoo]

How high (from the floor) do you plan to install the AP?

What's the wall and roof made of?

If you can sniff other people's 802.11b wireless then I'd recommend you disable 802.11b data rates and enable 802.11g.

[Kayle Miller]

Another consideration here is can you make use of the 802.11a bands?? Alot of laptop devices support it, but if your talking about only tablets, iPads, iPhones, and the like then you are restricted pretty much to the 802.11bg band only. If you are able in any level to take advantage of the 802.11a band you can double the clients per AP and really the number of clients per AP is more about the RF Bandwidth than it is anything else.

if you have 40 users just doing an e-mail check or light web surfing your fine per AP, but if you have 40 users trying to stream an HD movie from netflix you've got issues.

There are some arguements that in an environment you should disable the 802.11b data rates and potentially even disable 6, 9, 48, & 54mbps of the 802.11g rates leaving only 12, 18, 24, 36 enabled. But you have to be careful about whether you have the coverage for that scenario..

I'd think if you had 4-5 ap's you'd probably be ok.