StuntMonkeh

This is my very first post, little did I know how interesting all the information I have found was going to be when I typed 'wardriving' into Google that I had found on a page that did not describe its meaning !!

Now I have read enough posts on the forum to know that I will get shot down in flames if I do not do some legwork. This I am willing to do but I need a starting point like 'you need to find/calculate X'

I need to create a wifi link between an AP and a laptop that can communicate within a realitivly large building. I cannot specify how big but it would be upto say four floors within a max 50m footprint or typical office/hospital type building as this setup would be used only for a few days at a time at any one building. The laptop is likely to be used in most cases in a few set locations from the AP and comms needs to be setup quickly i.e: time=money. The AP is most likely to be situated within a plantroom on the basement, ground or top floor of the building.

Would just a cantenna type arrangement work if you could remember roughly where the AP is in relation to the laptop position?

I'm guessing what I am asking may not even be possible without a repeater somewhere.

Just finsihed writing my post and realised it could look a little suspect without a reason for this link. The wifi link is to be used when commissioning BMS control systems.

streaker69

First off, Cantenna's are COMPLETELY the wrong choice for this situation.

Second, if you're that unsure of what you're doing, it would probably be best if you hired a professional Wifi installer to come in and do a proper site survey and determine what would be the best configuration for your network.

After all, it's better to be the hero for getting it done right than the jerk that screwed it up.

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Thorn

Probably not.

That may work, but it's going to problematic for moving between installation jobs. which is what you seem to be doing if I'm reading between the lines correctly.

My suggestion would be to carry a pocket AP/router such as the DLink DWL-G730AP, and plug it into the nearest Cat5 outlet to where you will be working. That gives you the flexibility of wireless without having to go to extremes for short-term jobs. This is what I do when appropriate on various client sites. Although good old 50 ft. patch cord is many times easier to use, and is usually more secure.

Repeaters would probably not be appropriate at all. They are usually used in permanent installations, and that doesn't seem to be what you are talking about.

I gather that "BMS" is a British acronym for something like "Building Management System"? In other words, something to do with what is known here in the US as HVAC (Heating, Ventilating, and Air Conditioning)?

The reason I ask is that the only BMS acronym here that I know means "Baby-Making Sex" and I just can't see how that fits in with WiFi or control systems for office buildings or hospitals.

On word of caution: Make sure that you enable wireless security. Otherwise things such as user names and passwords can be sniffed over the air. You don't want someone else taking control of the heating later on because you were careless.

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Thorn
"Read Altas Shrugged. Compare it to today. Repeat as necessary"

StuntMonkeh

Yes thats correct, commissioning lasts only days.

The IT network on a building is usually still not up and running when we are commissioning so this is not really an option.

LOL, yea HVAC controls, didn't know about that acronym.

Well aware of that, but thanks for the advice.


I havn't been asked to do this by my work, it was simply a possible solution to something we have tried in the past with just an AP a laptop with internal wifi. Needless to say it was not too successful. It would just be handy for some instances, maybe I will look at cabling CAT5 to large amounts of remote plant.

Thanks for your input guys.

MikeP928

If I had to do this on a repeating basis with various building layouts, I would put together the following kit in a couple of portable boxes.

1 small ethernet switch
4 (insert your favorite brand) wireless access points. Not routers (or just turn off routing/dhcp functions).
1000' spool of cat5e cut and terminated into 200' lengths. 4 for APs and 1 for switch to existing network.
Power injection appropriate for the APs you are using. Screw POE.

That would give you the means to quickly drop cables down an elevator shaft (if legal) or drop it down the risers between wiring closets. Keep in mind that building codes vary, and in the U.S. many states are beginning to enforce codes against abandoning cable in buildings. Many local fire marshals are citing this as a violation.

The parts above would allow you to use NetStumbler (w/ correct card which I am sure you have already discovered in your searches) to quickly lay out a usable network to temporarily provide usable coverage.

As you discover how your coverage works out, add a couple of 5-9 omni antennas to the kit to boost weak points.

If time really is money, it should not be difficult to make a business case to acquire the equipment listed above. Then 2 men should be able to cover a building the size you described in the first morning of a new project.

4 of us put up a temp wireless network in the Orange County Convention Center in Orlando on the cat walks in 2 days. This included 50+ APs w/external antennas on 5' PVC extensions and 8000' of cat5 pulled back and dropped down the columns to the underground wiring and switches. We were having to terminate the RJ-45 connectors by holding a flashlight in out teeth to see the colors. 3 days later, we pulled it all out in 1 day. And yes, we got caught leaving the cat5 and had to pull and roll up 8000' feet of cat5. It's amazing how many garbage cans that fills up.


MikeP

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StuntMonkeh

Thanks for your input Mike, I have been sitting at work pondering the issue. I had thought about something like you described although usually the buildings are still pretty much building sites so laying cable around would not survive too well unless it was sheathed better. I think we would have to remove the cables after as I wouldn't have thought regs allow it and a client certainly wouldnt. An option would be to include in our price network cabling to the areas we want to use then the cabling could be pulled with the rest of cables and left permanent.

Had a bit of a read up on this, now I see why you say 'Screw POE'....LOL.

I think it looks like it could be done but would maybe take a few buildings to get a better idea of how to layout the AP's.