Wireless site survey

[KWestos]

Hi

I had a site survey yesterday to cover the whole school for wireless access. Please could you kind people clarify a few queries I have which resulted from this visit:

* I was told I would need access points in EVERY room - is this correct? The system I beleive they are pushing is the new netgear wireless (quite reasonably priced - I think about £1000 for the switch and £100 for the AP's. Each one of these has to be physically located into the wired network true? - I dont have POE capability (I was origionally told by the salesman these would just wirelessly pick up the central switch with no need to be connected to cabling.

* I need a managed setup for around £3000 - is this the best setup for the money?

* Also, I have heard of ZyXel - is this a good solution?

* In the mean time I need a very quick solution to a small laptop trolley. Is the HP Procurve 420 with access points any good?

Many thanks

[mrforgetful]

Definately a managed solution.

Do you know what your core switch is? Only reason I ask is with our HP Procurve 5308xl it is possible to buy an addin card to manage HP wireless APs.

As for each one being wired in I guess it depends, sounds the fastest most reliable method with the only other option really being repeaters.

[plexer]

Who did the survey and what did they use to do it?

Where they a company that specialises in wireless or just a network company that offers wireless.

If you have a scaled site plan companies like react technologies can use software from aruba to do a wireless power plan.

This would be backed up by a site survey to make sure the plan is accurate.

AP's in every room sounds a bit strange unless they are configured for no leakage whatsoever so they don't interfere with each other.

My whole wireless system is based around HP 420 access points with Airwave amp as the controller.

How many access points did the survey say you needed?

I've never seen a wireless network where the access points didn't need to be plugged into the network.

Ben

[KWestos]

Hi

Mr Forgetful - My core switch is a HP 5304XL
Plexer - the company I will not say, but they are a reseller who "do" wireless installations. I must say I was incredibly annoyed at the survey as all he did was walk round the building noting things down as to the estimate of wall thickness and room sizes. No measurements were made or a survey of any kind - just a visual!
Could you please expand on you're quote - "I've never seen a wireless network where the access points didn't need to be plugged into the network." I thought some AP's could connect wirelessly or piggybag off others to the main Wireless switch.

Many thanks

[HodgeHi]

Did you visit the stand at the Bett show?

If you didn't then they were promoting a managed system from the switch (£1100) to the APs (£100-£110 each). The guy gave me a talk and a demo of the system which i personally thought was quite good.

The APs are connect to the switch which centrally manages the APs and also powers them. The good thing about these AP's was that they were "clever" in that they detected load and then moved users to a second AP if it was too busy.

It also powered up and down signal strength if one AP was detected as offline, therefore covering the area that the offline access point would cover.

It also had a built-in "automatic site planner". You imported a floor plan into the switch with dimensions and then the switch apparently pointed out the optimal places for your access points to provide the best cover. The AP also provide seamless roaming. For the cash it didn't sound too bad although it is all just theory unless someone has used them already and can vouch for this system.

The system is of a collaboration between Netgear and Aruba.

[paul]

A proper survey company would use a piece of software to predict RF penetration dependent on wall construction, number of walls/floors. this would then be followed by a proper onsite survey testing the software's predicted results. May I suggest you opt for a company who’s background is RF as apposed to hardware/software. One AP per room seems excessive I’m also guessing they have not planned for RF bleed over from the adjacent AP’s which may also be on same frequency.

[plexer]

Well as I said all the wireless installations I've ever seen have a network point for the access point to plug into.

If this controller is powering them it is using power over ethernet and therefore requires a network socket at each access point location.

Ben

[plexer]

A quick google reveals all about the aruba netgear tie up I think.

Aruba released it access point code so that other manafacturers could make access points that can be configured with the aruba controller rather than restricting you to buying aruba access points.

Netgear is the first company to sign up to this and get its products certified.

The other thing also is that if all of your access points can not be reached by copper cabling from the location of the aruba controller you will need multiple controllers I believe.

Ben

[Adam]

I agree. We're doing our own site survey using wifi laptops and access points, and there's definately not a need to have one in every room. If you do have one in every room I imagine cross-talk is going to be a problem, as you've really only got 3 or 4 distinct channels that don't interfere with each other. So...... If you've got a square ish block of 4 average sized room the frequency overlap of the channels means you're probably going to have problems. Does that make sense?

[mrforgetful]

There's a Wireless Controller addin card for your Core Switch here but be warned, it is not cheap!

[joe90bass]

I agree. We're doing our own site survey using wifi laptops and access points, and there's definately not a need to have one in every room. If you do have one in every room I imagine cross-talk is going to be a problem, as you've really only got 3 or 4 distinct channels that don't interfere with each other. So...... If you've got a square ish block of 4 average sized room the frequency overlap of the channels means you're probably going to have problems. Does that make sense?

That's my understanding as well. We don't have APs in every room, and when the survey was done the guys used an AP and a laptop to test the strength in surrounding rooms.

[dhicks]

I thought some AP's could connect wirelessly or piggybag off others to the main Wireless switch.

Yes, a "repeater" can extend a wireless network without itself needing to be plugged into a wired network socket. This isn't a good solution for a school-wide system, though, as it uses up available bandwidth. Only good if you really can't get a network point to where you want it.

--
David Hicks

[petectid]

A proper survey company would use a piece of software to predict RF penetration dependent on wall construction, number of walls/floors. this would then be followed by a proper onsite survey testing the software's predicted results. May I suggest you opt for a company who’s background is RF.

I'm with Paul on this sounds to me like they did not carry out a wireless survey at all. Making notes of wall thickness seams senseless as the most important part of survey is whether the wireless signal can penetrate obstacles. Then to come back and say you need an AP in every room, what was the point of turning up for a survey, in most installations this would work. A wireless survey should involve wireless signals using different antenna to check their suitability in any one area of the site. Sounds to me like they want to sell you as much hardware as possible, and you probably do not need it.

[projector1]

get another angle on it, dlink do a free wireless survey and see what they recommend.
I think it's andrew taylor who looks after the education market.
We got them to do the survey and then bought 2100AP's and positioned then where instructed and on the channels recommended.

[chesswill]

Just out of interest how much did you pay for the survey, you mentioned that the company in question mentioned thet you should have an AP in each room, this will all depend on exactly what you are trying to acheive.

what exactly did the survey entail, and how long were they there for, i work for HS Dataline, and we offer the complete solutions.

We were exhibiting at the bettshow last week, on stand T27 long with a company called worldwide solutions, offering a VOIP communication devise that works entirely over the wireless network called Vocera.

If you are interested have a look at our website, and have a look at our portfolio,
www.hsdataline.co.uk or
www.educationalnetworks.co.uk