How many APs?

[jaf]

Hi, we currently have a site which has 70 APs, from Meru. I am just wondering whether this is about right for a site which has around 1400 staff and students, mainly desktop PCs which don't use the wireless, a couple of laptop trolleys and a few iPads. Staff use the wireless on their phones but to me this number seems excessive. The site is not particularly big and I would imagine that around half this number would be sufficient. Am I correct? I understand it is hard for you to judge not knowing the size of the site, and I know we need to do a wireless survey to accurately tell, just wondering if the number of APs is around what it should be or not.

 

Thanks for your help.

[zag]

We have 32 for our site which is 1100 staff + students.

 

Our site is pretty big and old.

[localzuk]

It is very difficult to judge, as we don't know the material make-up of the building, the local radio interference, or the size of the site. Also, what are the likely expansion plans for IT? More mobile devices? In which case you need high density.

 

In the last school I was in (metal framed new build), we had around that number of APs and it wasn't enough for the site for around that number of pupils. Signal propagation was terrible, so they needed to be everywhere. We had a survey just before I left and I came to the conclusion that we needed around 10 or so more APs to properly cover the site.

 

It also depends on the technology. With Ruckus, they generally do a better job of coverage. We have 15 APs here covering the entire site for 550 pupils. With a Cisco system we would have needed around double that (from a survey).

[Haptic]

Which model of Meru Access Point are you currently using?

 

As you mention it's hard to be fully accurate without a thorough site survey, not to mention dynamic factors such as device density, background RF etc which will all impact the amount of hardware required.

 

Thanks,

 

Mark

[PotNoodleTech]

45 cisco aps for ~65 classrooms. Site is old and spread out. A new school could probly get away with 30!

[Paid_Peanuts]

A post BSF school with 100 Cisco AP's off two controllers.

For a school of 1400 students, 200 staff and 75 classrooms.

[pcstru]

Without specific information on the exact circumstances it is almost impossible to say. However, those numbers don't make me think "someone is being scammed" they might make me think "difficult EM environment for the requirement".

[Chris_]

We have around 90 APs in a school with ~650 pupils. The school consists of quite a few large older buildings. We could do with a few more APs in some areas still.

[trekmad]

We have 55 Ruckus APs for around 200 staff and 830 students. We tap into the web interface of the Ruckus regularly and the maximum number of devices which are connected at any one time is around the 400 mark. Our building is old with some walls which are about 1m thick where new building have been built up to the existing and some sections with a large amount of metal framework. We are also a boarding school and have a large campus. We have 99% coverage and no issues with slow connections.

 

I assume you have a wireless controller and should be able to monitor the number of connections throughout the day and look at the loading history of each AP. You may find that you can lose an AP in certain areas and relocate to other heavily used areas.

[jaf]

Thanks very much for all your answers, it seems the best way forward is to do a site survey and see. However, the schools seems perfectly content with the amount of APs they have, although I feel it is excessive, as they think it is a bonus to have such good WiFi coverage. Of course I can see their point, however with so few WiFi devices at present and such high coverage of APs I can't see it financially makes sense. Anyway I will see if I can get a site survey done at some point, and what the plan is for more mobile devices. They are Meru AP 320s and 320i (mainly 320i).

[jamin100]

On the other side of that were a big ish site and cover the whole school with 16 unifi AP's

 

There was 32 ruckus ap's in just before Christmas and coverage a problem due to the age of the kit

 

We get around 150-180 on the wireless typically most pulling VDi sessions through

[fairm010]

On the other side of that were a big ish site and cover the whole school with 16 unifi AP's

 

There was 32 ruckus ap's in just before Christmas and coverage a problem due to the age of the kit

 

We get around 150-180 on the wireless typically most pulling VDi sessions through

 

Same here, large ish and covered by 15 unifi points.

[psydii]

I'm not sure what the benefit is to say "you have too many" ap's when they are now a sunk cost? And they probably don't.

 

Meru's selling piont is seemless roaming and high density. To pull that off you need complete coverage of the site in at least two channels (one in the 2.4Ghz and the other in 5Ghz bands). Roughly speaking (based on my experience across a few sites, and various vendors) this ball-parks to 1 ap per 2 classrooms + a few for awkward walls and unexplainable blackspots (Rule of thumb #1).

 

Rule of thumb #2: To get a good wireless experience (especially in a school with lots of logging off and on) you need -60dB everywhere.

 

Finally be aware that a site survey when you have meru installed looks quite different to other vendors in place. The "virtual port" (where your association actually roams between physical access points) means you will see far more 'aps' than actually exist, and they will all appear on the same channel.

[jaf]

OK I was probably too hasty in saying that it is too many APs, it was just my initial gut reaction that it seems like a lot. I started the thread just out of interest to see how many other people had so I could get a general consensus. You say they are a sunk cost - is there no way they could be sold back to the company we bought this from? I always thought that was possible... I guess in our case it's just excessive coverage for the mobile devices at present, but we shall see what the future holds for mobile devices at our school.

[KK20]

We have about 200 wireless devices with at least 33% in full active use at any one time. We use unifis - all LRs (2.4ghz no 5ghz). The main building is old and made of stone (eats signals very quickly). This has 6 APs per floor (24 in total) and there are still blackspots in certain areas (these arent used as student areas so I dont mind as much). The new building is made of glass and steel mainly, that only needs 8 APs spread over 3 floors (1,3,3 and 1 on an inner wall next to a window which covers the sports field by a surprising distance).