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Wireless Networks Causing Headaches For Businesses
ElvaWSJ writes "Wi-Fi was supposed to reduce complications, not create new ones. But in many offices Wi-Fi has been a headache. Like all radio signals, Wi-Fi is subject to interference. Its low power — less than even a typical cellphone — means that walls and cabinets can significantly reduce signal strength. Wi-Fi also creates networks that are more open than wired ones, raising security issues. And Wi-Fi has caused problems for virtual private networks. Some VPNs require a lot of processing power. If a wireless access point — at home, at the office, or on the road — isn't robust enough, a user often gets bumped off the connection."
Duh?
Make sure there are some bloody data ports where they are useful. The gods know how many office conference rooms I have walked into where there are two power/data/phone outlets on the far ends of the room behind heavy credenzas, instead of in the middle of the room accessible from the table top. Otherwise just blanket the place with WiFi and suck it up.
Not really, if you are a business that is deploying wifi as a solution to allow laptop users to move around fine, however if it is cheap solution to installing hard wired cables to each desk then someone needs to be re-informed about the pitfalls.
Wifi should be a supplement for larger areas with changing configurations (meeting rooms, conference rooms, etc) not as a replacement for a typical wired setup. Unless you plan on constantly rearranging your cubes, there's no reason to do that. Also you should think of the two networks as being completely separate and treat the wireless network as a public access point (i.e. force VPN access to the wired portion of your network).
I see the problem coming in where people think it's a wired replacement.
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Good thing it doesn't have to work over as great a distance as a cell phone then. It's almost as it it was designed that way!
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I used to do wireless mesh network algorythm development and we had (with 802.11b) acceptable, AES encrypted, coverage of a motor factory (think *lots* of wire and EM) with nodes running on 200mhz arm systems and 64mb of ram. No problems with VOIP either. You just need to do some (ok, expensive) system design and there's no reason why it wont work. In the demo system the nodes updated their routing tables using a ropey bash script even
Expecting that off the shelf gear can magically set itself up is the problem, not the protocol itself (which can be worked around in many interesting ways).
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It still might be cheaper, because in many (most?) cases you pay per drop and not per foot. If you're paying for both, it still might come out cheaper.
Of course, as you probably^Walmost certainly know already, WiFi is a better fit for edge conditions than it is for every computer in your network (even if you don't count servers.)
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gee i wonder why its crap ? 1) To keep the cost down. Even 'commercial-grade' access points use inexpensive components to help keep the costs down to the point that people can afford them. Compare the cost of ham radio -- and then consider if you would buy a WAP that had that amount tacked on the sale price.
2) Government regulation. Governments around the world regulate these 2.4 GHz-range frequencies and given the number of devices in the range, transmitter power is kept necessarily low by regulation.
3) To keep the equipment from interfering with other devices such as cellphones, 2.4Ghz-range walkie talkies, and countless other devices that use this frequency range. See #2.
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Oddly enough, with D-Link cards I've noticed that the third party connection software (D-Link Connection Manager) often works better than the Windows wireless network manager.
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At some point companies may wrap the exterior of the building with Faraday mesh to prevent radio signals from exiting the building with any significant range. External radio signals could be ported and broadcast within the building similar to the project to extend radio station signals into road tunnels as test in Pittsburgh, Pa. This would allow the company to control the signals that enter and exit the building while also allowing for cellphones and radios to work.
Now the cost to benefit ratio of such a system would most likely kills the idea unless the security of the network was highly valued.
"Things got so bad that Mr. Friemann sometimes had employees piggyback on a neighboring business's wireless connection that was more stable -- without the other business's consent or knowledge."
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Ok so your neighbor could set up a network which worked fine even for you whom, presumably, are further away from his source than you are from your own. Despite this its somehow the technologies fault? WiFi is fine, established, and mature this admins understanding of it is not.
and then there is this
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"Some wireless networking companies are taking steps to try to deal with customers' problems. One major issue is the stability of the wireless signal. Ruckus Wireless Inc., a wireless networking company based in Sunnyvale, Calif., tries to address that problem by providing wireless access points that have multiple antennas. That allows a Wi-Fi signal to have more than one pathway to an access point -- which can come in handy if something is in the way."
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Its called a cable folks, there are plenty of ways to rig antennas and get them in existing wap points. Thats not to say there is no value in what Ruckus is doing just that its not like we cant do that.
Before rolling out a big business wireless network, the installers should do a check of existing interference, then setup a simple access point/client and check it out in different places using a spectrum analyzer. Just like cable techs sometimes need a cat-5 analyser to trouble wiring plant problems, the wireless tech needs an instrument to measure the rf environment.
Heck, my wireless pda loses signal while standing near the microwave popping pop corn. Some buildings, especially in industrial areas, can get lousy with interference
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A tin-foil hat. The problem goes away.
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There's no good reason to use encryption in a corporate environment.
I mean, there's no reason to use client-to-accesspoint encryption. Instead you should be encrypting directly from the client to the VPN gateway.
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I have issues at home with this. The roof of my house is made of aluminum (not that cheap corrugated stuff like on a barn, but interlocking strips). This wreaks absolute HAVOC on WiFi signals inside my house.
If I put an access point at one end of the house, I can't pick it up AT ALL from the other end. I'm not talking microscopic SNR, I'm talking ZERO SNR. It's like I don't even have an access point. I'm lucky to get a quarter of the rated bandwidth if I'm only one room away.
For a while I had a ridiculous setup consisting of an access point and two repeaters just to get the signal to the other end of the house. TWO REPEATERS. That's THREE HOPS to travel about 100 feet. And of course, the concommitant loss in data rate due to the repeater action. After a few weeks of that (and even that setup was flaky at best) I said "Fuck it" and dragged a CAT-5e cable across the house. The wife hates it but at least I can use the Internet.
I have no idea how exactly the metal roof is destroying the signal, whether it is causing severe multipath or simply absorbing it completely, but it does it quite effectively.
That's not the actual worst thing. I can handle all the "access from anywhere", that was what it's designed to do. The worst thing is when the access point sometimes decides to reset (I have a Linksys AP) and it reverts back to it's original, OPEN SETTINGS. I go to work one day and I notice that the AP changed its ssid back to "linksys", giving free access to everyone within the radius for the past week.
Seriously, wtf.
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The gods know how many office conference rooms I have walked into where there are two power/data/phone outlets on the far ends of the room behind heavy credenzas, instead of in the middle of the room accessible from the table top.
:-)
Conference rooms are often populated by guests. I would not be surprised if your local security policy states that guests are not permitted to connect to the company network: having no easily-accessible jacks can be a decent physical security measure. Of course, this requires that guests not be left unattended, etc.
The placement of the credenza is either a calculated security move or a blunder of forehead-slapping magnitude, depending on your outlook.
I want to drag this out as long as possible. Bring me my protractor.
Rules of WiFi:
Put in dedicated services for visitors with instructions conspicuously posted in conference areas (along with sufficient power supplies.) Inform staff if they are caught using these open systems their devices will be taken away, and if they relied upon such to do their jobs they will then be unsuitable for continued employment.
Finally, consider alternatives to WiFi. There are any number of products that will carry WiFi-equivalent bandwidth over residential wiring. If youre looking to connect fixed devices without running ethernet then these are a no-hassle approach with competitive costs.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
I've done wireless assessments and installations for offices, hotels, school buildings (think bomb shelters) and even manufacturing plants. Anything IS possible, but not if you hire a kid recently graduated from ITT Tech(as an example only) to do it. I'd take a recent physicist graduate first because at least they would understand wave propagation. The use of tools such as Air Magnet make performing such an assessment easier, but a good tool won't fix ignorance.
This actually begs of a greater question within IT - that of the influx of semi-trained, unskilled workers. Ours is the only profession without a professional organization. We have no entrance exam, no licensing structure, no board review.
And DON'T tell me that Sylvan/Prometric certification in any sense means squat. I have no respect for a testing method wherein the correct answer is presented simply for the applicant to pick from. and YES I have them, many of them (MS, Novell, Solaris, Cisco) thus my disdain.
I think we as a profession need to adopt some form of 'guild' structure. 2-yrs as an apprentice followed by a board review WHERE YOU ACTUALLY PERFORM WORK(Think the CCIE practical exam where you configure otherwise blank routers) [Yeah I have that too]. 5-yrs as a journeyman where you expand and deepen your skill followed by another board review to obtain a Mastery level in a particular discipline.
The tradesmen have had this structure for hundreds of years. Lawyers, Doctors and Accountants all have an entrance exam.
Why do we in IT think we're different.
Just my $0.02
Dennis Dumont
That doesn't guarantee security. If you really want to take security seriously, post snipers on the roof and have them shoot employees before they can make it into the building.
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Of course, it goes without saying that encryption should always be used, the tighter the better!
mod be down you wankers
Won't some kind moderator please help out this poor poster? If I had mod points, I'd gladly help. -1 Offtopic, before you could answer the question, "mod be down with what?"
VPNs require exactly the same amount of processing power on an access point as any other network application. The access point doesn't encrypt or decrypt anything on a VPN. All it sees are packets and frames, regardless of the application.
Slow Down, Cowboy! It's been 60 minutes since you last successfully posted a comment.
First generation was "Thick" access points individually managed.
Second generation was the first generation of "Thin" access points.
Third generation is "Thin" access points using CAP-WAP tunneling to a central management platform.
For the First & Second generations we had consultants in to do surveys and radio measurements, we spent days roaming the site with radio gear and plans working out the best locations for the AP.
That turned out the be as much use as a chocolate teapot.
With the third generation (which is a forklift upgrade for the 1st & 2nd generation) we've gone with the scientific approach of "suck it and see". We ordered about 10% more access points than we had existing and when we've finished the install we'll go back round with our survey gear and fill in the dead spots.
Things I've learned from trying to get this right:-
Architects hate you They want the APs to be hidden, this is bad m'kay. Our second generation install we let the architects dictate where the APs could go. We've landed up with them 30' above the floor above a false ceiling. To maintain these we now have to close the building and get a cherry picker (which we're not allowed to use - it has to be a member of the facilities team) Outdoor coverage is a bitch. Lightning arresters, which are mandatory, cause significant loss as does "low loss" cable. Omni direction antennae are prety useless as generally you've got to mount them near a wall which nukes your signal. Directional ones are much better, but require more access points to get the same coverage. Things you wouldn't expect to impact the signal can bite you in the arse. UV filter glass (40db loss!), magnetic whiteboards, glass wall partitions. Out door it's even worse - forget it if you've got trees out there, oh and fog - fog kills the signal pretty dead. Never try to survey a building that's not there. This may seem obvious, but a lot of our installation had to be done from plans, so we had to estimate signal propagation - this doesn't work. Especially when the users of the building decided that what they really want is a nice metal mesh put into the walls, that really helps the signal. On the plus side - the 3rd generation ap & management station are making our life much easier. We can actually see where clients are now, and the APs know about each other and manage their radio intelligently (and it seems to work!)You shoot them if they try to LEAVE the building...if you shoot them before they get in, they can't do any work.
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In warehouses, people typically use handheld devices, today. They're much, much, much more reliable than wi-fi.
Nearly all of the wireless handheld devices used in warehouses have moved to 802.11. And it made life a whole lot easier when they did, no more proprietary protocols like we had in the 900 band.
If they seem more reliable, it's because they tend to be low data rate devices. At least I've never seen a forklift driver browsing multimedia web sites on their 3"x4" screens. The lower data rate allows them to fall back to slower speeds to overcome a poor signal without annoying the user.
BTW, if connectivity is important in a warehouse? With leaner inventories and management's desire for real-time information, I don't see how a modern warehouse could function without wireless devices.
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