Home networking explained, part 2: Optimizing your Wi-Fi network

Editors' note: This post is part of an ongoing series. For the other parts, check out the related stories, below.

Getting a Wi-Fi signal to every corner of your home can be a challenging task, especially if you have a large house or one with lots of thick walls. But there are things you can do to improve your Wi-Fi coverage.

Let's start with the ways that probably won't cost you anything, other than a little bit of time.

1. Placement

A wireless router (from here on, it will be referred to simply as a router) broadcasts Wi-Fi signals out in all directions. Think of the signal coverage as a globe with the router right at the center. Outside of this globe, clients won't get a signal. This globe, however, is not exactly spherical; one of the reasons is because the signals are generally tuned to disperse more horizontally than vertically, and like all radio signals, they tend to spread laterally and downward the farther they are from the transmitter. That said, the best place to locate your wireless router or access point is an elevated spot in the center of your home.

To take advantage of this, use a telephone jack (or coax cable outlet) at or near the center of the house, preferably on the upper floor when applicable, to connect to your modem and then your router. If need be, hire an electrician to install a new outlet in the right place. If it's not possible to move the phone jack or run coax cable to where you want, use a long network cable to connect the router to the modem, leaving the modem where the jack is and the router/access point at the center of the house. (In my experience, it's actually quite easy to run cables in the crawl space above the ceiling, or under the house.)

Surroundings: A wireless signal works best outdoors in an open environment. Since it's not possible to have that indoors, you can improve the signal a great deal by making sure the immediate surroundings of the router/modem are clear, especially in the directions you want the signal to reach. This means you don't want to leave the router in a closet, or put it between a big TV and a wall. The best place to leave the router is in midair, but since that's quite hard to do, the second best thing is to put it on the surface of a desk, or mount it on the wall when applicable. Generally, all physical objects, such as walls, glass doors and so on, weaken Wi-Fi signals, some more than others.

Antenna positioning: With a router that comes with external antennas, you can slightly tweak the above-mentioned globe of coverage. Generally you want the antennas oriented vertically if you want the signal to go wide (which is the most popular usage). If want the signal to go deep into the basement and up to the top floor, set the antennas to a more horizontal angle. Note that this only works relatively, and with some routers, you might not experience any difference at all regardless of which way you set its antennas.

If the antennas are detachable, it's likely that you can replace them with high-gain antennas (most of the time this means bigger ones), which noticeably helps increase coverage. You might also be able to increase the power of the antennas, hence the range, by attaching to it a piece of aluminum foil curled up into a parabolic shape.

For routers with an internal antenna design, there's not muvh you can do. Modern routers, especially N750, N900 and 802.11ac routers, however, generally come with very powerful and smart antennas that essentially increase their power toward the direction of connected clients automatically, using a technology called beamforming.

2. Equipment

Now, if you have placed your router properly and still don't find enough improvement, it's time to check the equipment. Get ready to spend some money.

Router: Ideally you just want to have one wireless broadcaster at home, and for most homes a single router is good enough. That said, if you have a small house and the router (put in the middle) can't cover every corner, it's time to consider replacing it. I'd recommend one from these lists.

Access point: A separate access point is an ideal solution for a large and sprawling home, one in which you can't place the router in its center, or one with a deep basement, with an existing router. Basically, you want to put the second access point in a location where the signal of the existing router can't reach or gets really weak. In a typical example of this setup, you would have the main router in the living room and the second access point in the basement.

Now the trick is to connect the access point to the router. Ideally, you should run a network cable from the router to the access point (you'll connect the access point's LAN port to one of the router's LAN ports). If this is too much of a job, you can resort to power-line networking.

Note: Many routers can also work as an access point and will indicate this in its list of features. In this case, the router's WAN port will work as a LAN port. In fact, for the secondary access point scenario, it's best to use two identical routers; one as the main and the second as an access point for the far side of the house. This way you don't have to learn about two different devices.

Power line: A power-line adapter basically turns your home's electrical wiring into network cables; this is more clearly explained in Part 1. In the case of the separate access point scenario above, you can use a pair of power-line adapters, such as the D-Link DHP-510AV. Connect one of the adapters to the router and the other to the access point, using network cables. After that, if you want to make your home network seamless, name the Wi-Fi network (or SSID) of the access point the same as that of the existing router. In this case, make sure you use the same security settings (encryption key, method and so on). Or you can also keep them as two separate Wi-Fi networks for easy management.

There are also power-line adapter kits with a built-in access point, called power-line range extenders, such as the Netgear XAVNB2001. In this case, you don't need to get the second access point/router.

In addition to power line, you can also opt for a pair of MoCA adapters. MoCA stands for Multimedia over Coax Alliance, and similar to power line, turns coax cables (those used by cable TV) into network cables. MoCA adapters are great solutions for homes with multiple cable outlets in different rooms. I don't have a lot of experience with MoCA, however, since it's not possible to test those at my office.

Range extender/repeater: These are wireless devices that can connect to an existing Wi-Fi network and then rebroadcast that same network's signal farther. Most of these devices support Wi-Fi Protected Setup and can connect to the existing router with the push of a button; after that, you can just put one at the edge of the existing network's Wi-Fi range and have that range increased.

I am not a fan of this type of device for a few reasons:

First, it's hard to gauge its effectiveness. You need to put a range extender/repeater relatively close to the existing router for it to have a good connection with the main network, but at the same time far enough for it to really extend the range. It's very hard to find the sweet spot for it to be effective both in terms of range and connection quality.

Second, the repeater basically duplicates the existing Wi-Fi network with one of its own, and as mentioned above, Wi-Fi signals are broadcast in all directions. This means devices in the area where the two networks overlap have to deal with interference and signal saturation. This is especially bad for the 2.4GHz band.

That said, a range extender/repeater is still the fastest way to relatively extend a Wi-Fi network's coverage.

3. Settings

One of the problems with Wi-Fi networks is the risk of losing your bandwidth to unauthorized users. This part helps you secure your network and optimize it for speed. Note that it's slightly more advanced and might seem intimidating to novice users. But you will be a novice no more if you follow through with it. This part is only recommended for those interested in learning more about networking.

Rule of thumb: Make sure you back up the router's configuration settings before making changes. This allows you to restore it to previous settings in case something goes wrong.

With the exception of networking products from Apple, most, if not all, other routers and access points on the market come with a Web interface. This means that from a connected computer, you can open up the router's management Web page by going to its IP address. Unless you have changed it, the default IP address is generally printed on the bottom of the router, or on its user guide, and tends to be in this format: 192.168.x.1.

It's easy to find out your router's IP address. Here are the common steps to get to any home network's router's Web interface:

1. From a connected computer (running Windows Vista or 7), click on Start button, type "cmd" in the search area, then press Enter. (If you use Windows XP, you can navigate the Start Menu and run the Command Prompt item.)
2. Now in the black command prompt window, type in "ipconfig" then press Enter. You will see lots of information displayed in the window. Find the string of numbers that follows "Default Gateway" -- that's the router's IP address.
3. Type that IP address in the address bar of a browser such as Chrome or Firefox, and press Enter; now you are at the router's Web interface. You will have to log in with an account. The username is almost always admin; for the password, check the router's manual or ask the person who first set up the network for you.

On the Web interface, the following wireless settings will help your network stay safe:

Network name and password: Most if not all routers come with a default Wi-Fi network name (or SSID) and password; you won't want to use those. This is mostly because that reveals to advanced users which router you have and that, well, you don't know much about networking. Changing the SSID and password to your preference also helps you remember them better.

Use WPA 2: Using the WPA 2 encryption method helps both increase the security and the speed of the Wi-Fi signal. The only catch is that WPA 2 might not be compatible with older clients. All new clients released in the past few years support WPA 2, however. You can try using WPA 2 first, and if some of your clients are unable to connect, switch it back to WPA.

In addition, once you have accessed the router's Web interface, there are many other settings that you can try. For safety, there are also MAC address filters, Internet filtering and so on. Note that a router generally takes about a minute to restart to apply new settings.

To learn how to make your own networking hardware, check out Part 3 of this series.