NorthShore Computer Services

Home Network Tips
• Place routers up high
A wireless router with an integrated access point (AP) or an AP all by itself should be placed as centrally in a house or office as possible to provide the best signal. Put it up high—even mount it on the wall—not down low and definitely not under a desk.

• Avoid radio signal bounce
Metal objects like big filing cabinets or cement walls can cause interference for wireless network signals, so try to keep your router/AP away from them. Even the slightest move could change the way the radio signals bounce.

• Change default settings
Change the default username and password on the router. They're usually the same on every router from the same manufacturer. Same with the service set identifier (SSID) of the Wi-Fi network. Linksys, for instance, defaults to a Wi-Fi network called "Linksys" or some variation. Not changing it can signal to snoops that the network may be wide open.

• Limit Wi-Fi conflicts
Be sure the channels on an 802.11b/g network are set to 1, 6, or 11 (check your manual to find out how). Those are the only three channels usable in the United States that don't overlap. Channels that overlap other Wi-Fi networks can cause interference.

• Look for interfering networks
If you suspect interference—for example, if your once fast network seems slooow—see if your laptop can see networks other than your own. Someone nearby may have a network on the same channel. Check with your neighbors to find out which channels they are using, and make a switch if needed.

• Upgrade to better security
If you're concerned about security but still use Wired Equivalent Privacy (WEP) for encryption, you're not concerned enough. WEP is easily cracked by anyone with the time and the easy-to-find tools. Upgrade your software/firmware (and hardware if necessary) to use Wi-Fi Protected Access 2 (WPA2), and use a long, strong password. That will make it almost impenetrable.

• Mix dynamic and static IPs
Mix your use of DHCP's rotating addresses with static IP address: Assign static IPs for your own computers, and reserve a limited pool of DHCP addresses for guests.

• Skip the CD setup
Many Wi-Fi vendors provide a CD for accessing router features. You won't need it. If you know the router's IP address—typically—just type that into the Web browser of any PC that gets its IP address from the router. The Web-based controls for the router will be at your finger-tips once you enter the router's username and password.

• Share less in public
When you connect to a network with Vista, you have to specify whether it's Home, Work, or Public. If it's an unsecured Public network, the Vista Public folders are not shared, strangely enough; they would be shared on a Home network, however. Turn sharing on or off manually in Vista's Network and Sharing Center, accessed with a right click on the network icon in the system tray.

• Firewalls can block shared PCs
If two computers on the same network refuse to see each other for sharing files or printers, temporarily deactivate any software firewalls you've got running. If the connection works, you know the culprit. Enter the IP address for the entire network on each firewall to allow continued access.

• Limit dynamic IP addresses
The Dynamic Host Configuration Protocol (DHCP) assigns IP address in a range to all the devices that connect to your server, whether it's wired or wireless. You can limit the number of connections by reducing the range in the router settings; you can also turn DHCP off. If you do, you'll have to assign a static IP address to each device manually. Static IPs don't change, which might be important for sharing.

• Reserve IP addresses
Using DHCP means sometimes your computer changes IP addresses, depending on when an address renews ( one day, but .104 the next). You can use static IPs to solve this, but better yet, use the "DHCP reservations" feature some new routers provide. It matches a specific IP address with the unique MAC address of a computer's network adapter, so the IP address, even though it's a dynamic IP, never changes.

• Find the MAC address
You can find your network adapter's MAC address (called the "physical address") and the IP address (either dynamic or static) by opening up a Windows command line (at the Start menu, go to Run, then type cmd) and typing ipconfig /all.

• Avoid 2.4-GHz competition
Interference can come from other items using the same radio spectrum. 802.11b/g uses the 2.4-GHz frequency—and so do many cordless phones and even microwave ovens. If your Internet access goes out when you're heating a burrito in the microwave, move the laptop out of the kitchen. If you can afford it, switch to a router with 802.11n supporting both 5-GHz and 2.4-GHz, and reserve the 5-GHz side for your most important connections.

• Avoid IP address conflicts
Two computers sharing the same IP address will cause a conflict. With DHCP, try to set a range of IPs that would be unlikely to be used (say to .250). If your PC has a conflicting address, in the command line type ipconfig /release, then type ipconfig /renew to receive a new one from the router's DHCP server.

• Third-party DNS adds features
DNS servers are assigned by your ISP; they convert the IP addresses used to communicate over the Internet (such as into easy-to-remember URLs. OpenDNS ( replaces a default DNS, speeding up queries a touch and provides extras like phishing filters. Find the DNS settings in your router's Web-based interface and replace them with and, then sign up for an account to get the extras.