Zolton,

I have to ask- is what you in place the result of a legitimate design and some 
definition of requirements? If anything, you have a pretty sizeable 
overabundance of APs in the lecture halls. Since you're asking, I'll give my 
opinion, qualifying that it might change (slightly) if I could actually see the 
spaces or hear what clients are actually doing when connected. You didn't 
mention whether these are ceiling or wall mount, which also comes into play. 
But regardless, here's what I think is causing you issues, fundamentally:

Lecture Hall 1: for 250 users/400 expected connections, 10 APs *sounds* absurd. 
These are dual-band APs, and you are going to have clients half and half on 2.4 
GHz and 5 GHz (+/- 15%) which means you have 20 cells in one room, not counting 
what bleeds in from adjacent spaces. You probably could service this space with 
three 2.4 GHz cells, and between three-five 5 GHz cells (and some on the list 
would still say that's overkill). 

Other two lecture rooms- same thing. No more than three in 2.4 GHz, 3-4 in 5 
GHz.

On to your other stuff:

In order to minimize the co-channel interference, we have implemented the 
following:

1- Removed 40 Mhz and 80 MHz bandwidth modes and set everything to 20 Mhz. 
EXCELLENT
2- Removed G on all our access points. HELPFUL, BUT NOT YOUR BIGGEST PROBLEM
3- Implemented band steering. REMEMBER, NOT ALL CLIENTS WILL RESPOND SAME WAY. 
BEST TO HAVE HEALTHY RF FIRST.
4- We are now in the process of manually adjusting the 2.4 Ghz channels on each 
AP so the neighboring APs do not have the same channel. In some cases, we turn 
off the 2.4 Ghz completely. GOOD


Would you please comment on the following?

1- With the current hardware that we have is it advisable to proceed on this 
route and configure the 2.4 Ghz manually? ABSOLUTELY- BOTH CHANNEL AND POWER IN 
THESE SPACES
2- Should we completely disable 2.4 Ghz support? Is it a norm for high density 
areas? NO- BUT HAT YOU HAVE IS LIKELY UNUSEABLE IN SPOTS AS DESCRIBED
3- Should we look to change hardware/ or vendor in order to have a seamless 
environment. Should we just limit the change to the high density areas or 
should we just change it overall. CHANGE NOTHING BUT YOUR APPROACH- THIS IS NOT 
A HW SELECTION PROBLEM- IT"S A DESIGN DEFICIENCY
4- Is a single channel solution for the lecture halls advisable? Have you 
experience a mix of single/multi-channel environment? How do they perform? 
SWEET CHEESE NO. YOU THINK YOU HAVE PROBLEMS NOW!

Absolutely do not run two vendors in your environment. You are using decent 
components now, changing the brand but duplicating this design will net you the 
exact same issues again. Solve your basic "too many APs issue" and your  
current hardware will serve you well.  Sooner or later you will overrun that 
500 Mbps to the Internet, so that bears watching.

Kind regards,

Lee


Lee Badman | CWNE #200 | Network Architect 

Information Technology Services
206 Machinery Hall
120 Smith Drive
Syracuse, New York 13244
t 315.443.3003   f 315.443.4325   e [email protected] w its.syr.edu
SYRACUSE UNIVERSITY
syr.edu


-----Original Message-----
From: The EDUCAUSE Wireless Issues Constituent Group Listserv 
[mailto:[email protected]] On Behalf Of Zoltan Toth
Sent: Tuesday, November 22, 2016 10:35 AM
To: [email protected]
Subject: Re: [WIRELESS-LAN] High-Density Lecture Halls

Hello,

Thanks for your response.


We are currently running our Wi-Fi environment on HP 860 Wi-Fi Controller 
configured for high availability failover, with approx. 92 access points of the 
model HP 460 and 466 and 560 spread across the campus. The campus is separated 
into 3 floors with 3 high density areas namely lecture hall 1 with a seating 
capacity of 250 with about 400 connections (10 model 560 APs) and lecture hall 
2 with a seating capacity of 197 (6 model 560 APs) and a general hall with 
seating capacity for 200 (4 model 466APs). We have a 10 GB backbone an all 
switches and a 500MB internet connection. We are running PRTG to monitor the 
bandwidth consumption at the backbone and internet level and do not see any 
bottlenecks.


We have conducted a Wi-Fi survey and have their report which mentioned 
co-channel interference in the 2.4Ghz band. According to the survey the Wi-Fi 
signal coverage seems to be present in most of the campus areas.

In order to minimize the co-channel interference, we have implemented the 
following:

1- Removed 40 Mhz and 80 MHz bandwidth modes and set everything to 20 Mhz.
2- Removed G on all our access points.
3- Implemented band steering.
4- We are now in the process of manually adjusting the 2.4 Ghz channels on each 
AP so the neighboring APs do not have the same channel. In some cases, we turn 
off the 2.4 Ghz completely.


Would you please comment on the following?

1- With the current hardware that we have is it advisable to proceed on this 
route and configure the 2.4 Ghz manually?
2- Should we completely disable 2.4 Ghz support? Is it a norm for high density 
areas?
3- Should we look to change hardware/ or vendor in order to have a seamless 
environment. Should we just limit the change to the high density areas or 
should we just change it overall.
4- Is a single channel solution for the lecture halls advisable? Have you 
experience a mix of single/multi-channel environment? How do they perform?

Zoltan
__________________________________________
Zoltan Toth - Manager, IT Infrastructure
Canadian Memorial Chiropractic College






On 2016-11-18, 11:11 AM, "The EDUCAUSE Wireless Issues Constituent Group 
Listserv on behalf of Lee H Badman" <[email protected] on 
behalf of [email protected]> wrote:

>Hi Zoltan,
>
>I'm assuming you're asking about wireless infrastructure and not client 
>devices? If so, I would say it's more about proper design than any different 
>technology.
>
>Also assuming that the lecture halls are in the mix with adjacent areas that 
>also part of the overall WLAN environment, you're generally limited to what 
>your current vendor (and code) support as opposed to trying to run islands of 
>different technology from Vendor B in the middle of Vendor A WLAN.
>
>Which brings us back to design. In a perfect world, you'd have some sense of 
>what type of client devices are likely to be in those rooms, how many active 
>at a time, and what they might be doing. For modern APs, you might service 
>200-300 "people" with 2-3 APs with captive antennas spaced and oriented 
>properly (depending on room layout), or you may need double that with 
>extremely low power and directional antennas.
>
>So... the answer is "it depends", as with all things wireless.
>
>Regards-
>
>Lee
>
>Lee Badman | CWNE #200 | Network Architect
>
>Information Technology Services
>206 Machinery Hall
>120 Smith Drive
>Syracuse, New York 13244
>t 315.443.3003   f 315.443.4325   e [email protected] w its.syr.edu
>SYRACUSE UNIVERSITY
>syr.edu
>
>
>-----Original Message-----
>From: The EDUCAUSE Wireless Issues Constituent Group Listserv 
>[mailto:[email protected]] On Behalf Of Zoltan Toth
>Sent: Friday, November 18, 2016 9:47 AM
>To: [email protected]
>Subject: [WIRELESS-LAN] High-Density Lecture Halls
>
>What technologies do you use for high density areas like Lecture Halls for 
>about 200-300 people?
>
>__________________________________________
>Zoltan Toth - Manager, IT Infrastructure
>Canadian Memorial Chiropractic College
>
>
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