Beating the wireless blues
- — 09 April, 2004 15:00
Extend your network's limits
When you want to spread a wireless network wider than the maximum range of a single gateway, you have a number of options. The cheapest ($35 to $80) and best alternative is to add more Wi-Fi gateways. Access points contain just a Wi-Fi radio, and as a result are simpler to configure and troubleshoot, but they often cost a little more than a gateway.
If you can run wires through walls or under floors, ethernet can link more than one gateway in a network, creating a much larger bubble of connectivity. Another option, called a wireless distribution system (WDS), lets you daisy-chain Wi-Fi gateways wirelessly. With WDS, a gateway in your home office, for example, can talk to another one halfway across the house, and that one can talk to a third gateway in the front of the house.
WDS is also known as wireless bridging, because traffic from each gateway is connected (bridged) to other gateways. But since WDS isn't a standard, not all gateways support WDS, and the system works differently in different manufacturers' devices. If you want to use WDS, it's safest to buy all your gateways from the same company. Buffalo's WBR-G54 ($85 to $110) and Apple's AirPort Extreme Base Station ($199) are good examples of WDS-enabled gateways with full Windows compatibility.
Whether you use gateways or access points, if you set up the WDS bridges incorrectly, you can cause more headaches. Eric Myerson of Los Angeles learned that lesson the hard way when he tried to bridge three access points: They talked in circles to one another, never reaching the Internet. "Figuring this out was quite frustrating," Myerson said.
In a typical home or office, you should set up one smart wireless gateway to bridge your wired network to wireless clients, to act as a firewall, and (optionally) to issue an IP address to any computer that connects to the network using DHCP (Dynamic Host Configuration Protocol). You want only one gateway to offer these features as your barrier and link between the Internet and your internal network.
The other gateways should be dumb, with all features other than the wireless access point disabled. (Problems will very likely crop up if more than one gateway has its DHCP server enabled. Run the DHCP server only on the gateway that connects directly to the Internet.)
Another way to extend the reach of your wireless network is to use a HomePlug product, which routes data over power lines. You could connect two relatively distant gateways within a single building to fill in any dead spots in your wireless network. To do so, you would attach the network cable from one gateway to a HomePlug adapter in one room, plug the adapter into a power outlet, plug in another HomePlug adapter in a distant room, and then connect the network cable from the second HomePlug adapter to the second gateway. Some companies even sell HomePlug-to-Wi-Fi adapters, which eliminate the need for another gateway.
HomePlug's main limitation is that it doesn't work over isolated circuits -- power outlets wired directly to the circuit breaker -- which might restrict its use in newer homes and buildings, where you're more likely to find such circuits.
