It sounds crazy, but 95 percent of all Internet connectivity problems can be solved by power-cycling both the router and the modem. Turn them both off, and then turn the modem back on first. Once its "sync" or signal light comes on, turn on your router.
You've probably heard this before, but it bears repeating: Always enable your router's wireless security! Wired Equivalent Privacy (WEP) encryption is the oldest (and weakest) form of security; the newer (and stronger) Wi-Fi Protected Access (WPA) and WPA-2 are the best protection available today for home users.
All routers include internal read-only chips with embedded instructions that can be updated by the manufacturer. Router manufacturers generally update a product's firmware to increase performance as well as to resolve bugs and security issues, so it's wise to keep your router's firmware up-to-date. Check the manufacturer's Web site for the latest updates.
If walls and distance are causing wireless signal degradation, you can do a few things to boost it. Move your router to higher ground—the signal radiates downward. You can also try a signal extender (or repeater), which boosts the signal. Finally, high-gain antennas will work, but they only focus the signal in one direction.
Every router has a well-known default password that's used to access the router's browser-based configuration page. Most setup wizards will make you change this password, but not all do. If not, be sure to change it yourself to prevent unwanted hangers-on from changing your network's settings.
If you've lost or forgotten your router's login credentials, you can get around this predicament by resetting the router to its factory settings. Do this by holding down the button on the back of it for 30 seconds. Next, look in the manual for the default user name and password, and then change them on your router's browser-based configuration page.
Unless you disable it, your router broadcasts its service set identifier (SSID)—the name of your network—which allows your neighbors to see (and attempt to gain access to) your network. Instead, disable broadcasting, making the network appear as "SSID not broadcast." Access the unnamed network by typing in the SSID name when prompted.
Change your pre-defined, default SSID—leaving it as "Linksys," for example, tells the world that you haven't configured your router, which invites attackers.
Every piece of networking gear includes a unique "fingerprint" called a media access control, or MAC, address. You can configure your router to filter connections using these addresses so that only your computers can connect to your network. Most routers will show you connected devices, so adding an adapter's MAC address is a one-click process.
The majority of today's networks operate in the crowded 2.4GHz frequency range, which is shared by microwaves, cordless phones, and other home networks. To avoid possible interference, many new routers are capable of broadcasting at 5GHz, which has 23 wide-open channels as opposed to 2.4GHz's three non-overlapping channels.
Most people use their router as a DHCP server; when clients connect, the router dynamically assigns IP addresses from a large pool of addresses. Limiting that list to the number of clients in your home, however, will help prevent interlopers from hopping onto your network.
Two features make most hardware firewalls more powerful than software firewalls: stateful packet inspection (SPI) and network address translation (NAT). SPI examines packets' content and behavior before granting access, and NAT hides all PCs connected to the router from the Internet, "translating" their IP addresses into private ones that are unreachable from outside the firewall.
Wireless B and G (and some N) routers operate at the 2.4GHz frequency, which only has three non-overlapping channels: 1, 6 and 11. By default, your router will most likely be using one of these channels, and the bad news is so your neighbors' routers as well. If you experience dropped connections, sluggish performance or both, a good first step is to switch the channel. If it's set to channel 1, go to 11. If it's set to 6, try either 1 or 11 for best results.
If a network adapter's software takes control of your wireless network, it can be difficult to put Windows back in charge. First, click Start, then Run, then type services.msc. Scroll down to Wireless Zero Configuration and start the service. Right-click your wireless connection, select view available networks, and then click advanced settings on the left. Click the wireless networks tab, and check "Use Windows to Configure my wireless network settings."
If you're in a public place with a Net connection, it's a good idea to disable File and Printer Sharing for Microsoft Networks. In the properties of your network adapter, uncheck the appropriate box. It's also a good idea to switch your notebook's wireless radio off if you aren't using it.