Pros/Cons of wireless LAN

Cisco and Compaq both are breaking out the cards and switches. I have installed and used the Cisco 10Mb wireless card and switch. It seems to work well within 150 to 200 yards. You could try the following link for reading material. I have seen the link go offline and the clients computer hang for a few minutes util the client moved to a better range.

http://www.cisco.com/warp/public/779/smbiz/netsolutions/find/wireless.shtml

http://www.cisco.com/warp/public/cc/pd/witc/ao340ap/prodlit/airo_ov.htm

Shane

Sounds exactly like the situation that the wireless folks are pushing - retrofits. The thick floors will require some on-site experimenting. If you can find a supplier who can use you as advertising, or if your order is big enough, they will come out with some trial.

I would assume that you will be effectively "zoned" per floor as the signal strength isn't enough to push through that much concrete. That means you'll only have to punch holes and run cable between floors.

I've only put up a home wireless LAN. It was a complete dunk - 30 minutes to set up - and has worked smooth since, but there's no real comparison.

One of our schools was built in 1901 (well, part of it was). We have old, thick walls and floors. Wireless networking people keep telling me that I have the right case for wireless, but they are wrong. Here's why.

I bought some Lucent gear anddid some testing. Reception in the same room was fine. But leaving the room dropped me from 11 Mbps to 5.5 Mbps. I could go maybe 100 ft. down the hall and stay at 5.5 Mbps. In the next room, I stayed at 5.5 Mbps. However, if I went to any roomother than the one right next door, I got no signal.

Let's say I could live with 5.5 Mbps (which is going to give me maybe 3 Mbps throughput). I'd still have to have an access point in every other room. So now I'm looking at paying $500 for an AP in every other room (OK, $250 if I went AirPort). And for every computer, $150 for a NIC, plus $40 for the PCI adapter if I'm putting it in a desktop. And that's getting me less bandwidth than I would with a 10 Mbps hub. And I'm still running awire to every other room to connect the APs to each other. And I have no upgrade path.

Instead, run one wire to each room at about $120 per run, then put a switch in there, and connect any computers in that room to the switch. Now I'm running at 100 Mbps switched. Bandwidth a problem? Run two wires to each room, trunk them, and that room can connect to your backbone at 200 Mbps. Got more money? Run a fiber to each room and go 1 Gbps to the backbone.

One vendor suggested I put APs along the hallway and wirelessly bridge them together. That works nicely for my connection to home (I'm only 300 ft. from the school), but if I put 8 APs in a hallway, then 8 of the 14 possible channels are gone to make my "backbone." So I've got to hope that the signals degrade enough that the 6 other channels is enough. And if the signals leak through the floor.... And if you read the literature, Cisco and Lucent recommend keeping multiple channels as far apart as possible, so using all 14 channels is going to degrade performance anyway.

And now I have an 11 Mbps (6 Mbps effective throughput) shared backbone with no upgrade possibility.

Suddenly, all the surface raceways don't look so ugly. You'll have some anyway, to link the APs, so just make it a little bigger and run more wire.

In my experience, wireless is useful in several niches (great for a cheap connection between buildings, inside a warehouse, if your users are constantly using their computer all over the building, etc.). But if what you have is a few desktops in each room, wireless is going to be expensive, and you'll throw everything out in two years because someone will ask for video or voice, and your infrastructure won't handle it. Cat5 cable will last you for years, and fiber is forever. You just swap out the switches when the price gets attractive.

Oh, and since the 2.4 GHz spectrum is unlicensed, any manufacturer can create a device transmitting in that range. Bluetooth devices, for instance, use the 2.4 GHz range, and from what I've read, a single Bluetooth device will drop 802.11b throughput by 75% in whatever room it enters. One person with a Bluetooth PDA becomes a rolling data blackout.

And then there's security. I wouldn't want my divorce proceeding sent over an 802.11b; the encryption isn't that good.

I use wireless. I love wireless. But it's not the solution for most situations.

If you're still thinking about it, buy one access point and one NIC, fire up the access point, and walk around the building with the NIC in a laptop (both Lucent and Cisco cards come with software that shows you signal strength).

If you are in a structure that does not lend to easy cabling, or you don't own the building, then wireless can make a big difference. Most especially if you decide you may move someday. With wireless, you can take your network with you.

Lucent has a high end wireless solution that we have installed in a historic building. considering our options for drilling holes was very limited and extremely costly as we would have to drill through thick walls. The Lucent option saved money and is verystable.

I'm assuming that since the building is 100 years old, even minor construction work is out of the question, so you can't run cables through the floors between storeys, instead you would have to go through a window.
Since the walls are so thick, youwill lose signal strength very quickly, as previously mentioned. If you must cable between offices, trllowing heating pipes as there is normally sufficent room around these to run a cable.
The main problem with Wireless is that if any obstruction is placed between the transmitter and reciever, no matter what it is, the signal will be distorted or weakened, so all routers and switches need to be mounted under the ceiling, above head height. It really is a problem, resulting in many stresful hours, trying to install a wireless LAN and then convince the office staff they cannot change the office layout, for fear of blocking a router.
Stick with cables, I would.