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Originally published at Internet.com
In my office, I have a cable modem that provides high-speed Internet access for two computers. The cable modem connects to a D-Link AirPlus Xtreme G DI-624 4-Port Wireless Router. One PC connects to the router using an RJ-45 cable, the other to a D-Link AirPlus Xtreme G DWL-G520 Wireless PCI Adapter, which resides about 80 feet from the router.
On the computer using the RJ-45 connection, my Internet connection runs quite fast, yet the computer with the wireless connection suffers from extreme lag times. For example, when I am talking on AIM, I won't get any messages for about five minutes, and then suddenly, a bunch of messages appear. Response time while browsing Web sites is also painfully slow at times.
The strange part is that, according to the diagnostic utility included with the D-Link wireless card, the signal strength is very good. The speed usually registers high, but at times, can fluctuate dramatically.
Could the problem be that our office is in a 40-year old cinder block building? The wireless computer is also separated from the router by a few walls, which might cause interference. Is there anything I can do to fix this problem, or would I be better off running a line to the second PC and forgoing the wireless network? Thanks for all of your assistance.
Obviously, the most reliable thing you can do is to run a wired line to the second PC. If this is an option for you, then it certainly bears consideration. Even with all of the advances made in wireless network technology over the last few years, wired networks still have many advantages going for it.
For starters, they aren't prone to any of the interference issues that wireless networks suffer from, and they're at least 10 times quicker than an 802.11g wireless connection. Wired networks are also far more secure, so you don't need to concern yourself with things like WEP encryption or SID broadcasting.
The downside to a wired network is that it can sometimes be very difficult to run lines where you need access - particularly in a cinder block building like yours. This means bringing in qualified people to run the lines and check their integrity or simply running long cables throughout the office in a somewhat haphazard manner. Fortunately, there are several options to try before you're faced with hard-wiring your office.
Normally, 80 feet between the router and the wireless computer shouldn't be a problem. The typical operating range of an indoor wireless network should be around 100 feet (maybe more in an open area like an auditorium). However, as you mentioned, steel beams within the building, concrete and even glass can all contribute to a decrease in signal distance. Plus, as the distance between the router and the wireless card increases, the signal strength weakens and the speed drops.
The fact that your transmission rate has a tendency to drop significantly from time-to-time leads me to believe that something's generating interference on the same frequency as your wireless network. There are a number of things that could cause this: microwaves and wireless phones being two examples. Check to see if any of these are in use when wireless problems occur. A while back Wi-Fi Planet (one of our sister sites) did a story on this type of problem. If you're curious, you can read it here.
If you share office space with other companies that also run wireless networks, that might cause problems. If that's the case, try broadcasting on a different channell. Channels range from 1-11. Also, take a peek at the router settings and see if your SSID is being broadcast. If you're not using WEP encryption and didn't bother changing your default admin password, it's possible that somebody might be mooching off your bandwidth.
You cal also try moving the PC to a different part of the room to see if the reception improves, or place the router higher in relation to the computer to try and compensate for the signal weakness. Also, a virus on the wireless PC could cause the problems you're experiencing. It might seem unlikely, as I'm sure you're running anti-virus software, but it's worth checking.
If after trying all of these options you still have problems and feel that the distance is what's affecting your performance then buy a repeater. You see, when you first broadcast a digital signal it is very strong. As it continues to travel away from its source, the signal strength weakens. The further the signal travels, the weaker it becomes; until finally it looses its integrity. This is referred to as attenuation.
A repeater picks up this weakened signal, regenerates it and then rebroadcasts it, extending the range of your network. This regeneration also makes the signal stronger, making it possible to overcome some of the interference you might be encountering from the concrete walls. After you've configured the repeater to work with your network, simply plug it in somewhere between the router and the wireless PC. This should be enough to increase your wireless network's signal strength and hopefully relieve you problem.
As a last resort you could always try contacting D-Link Tech Support for help. D-Link should be able to help you determine that everything is installed correctly and that you're using the most current firmware. I hope this helps!
Adapted from PracticallyNetworked.com, part of the EarthWeb.com Network.
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Author: Ronald V. Pacchiano
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