A router is a device that moves packets of data between computer networks. Usually, the router connects a local area network (LAN), such as in a home or office, to a wide area network (WAN), which can be a cable modem or digital service line (DSL) modem. In the simplest terms, for its most common use, a router is the traffic cop between a computer or network and the Internet. A wireless LAN router (WLAN) adds extra functionality to the router, allowing wireless access to it from devices equipped with wireless network or WLAN cards.
Routers typically contain multiple ethernet ports so that multiple computers and devices can be attached to it. A WLAN router will have this same functionality, but in addition, it contains an 802.11 wireless access point. This means that the number of devices that can be attached wirelessly to the router is limited only by the bandwidth of the WAN it is connected to.
In a home environment, where the user will be connecting to a cable modem or DSL modem, many of which only have one open port, a router might be the best option. Many cable and phone companies, however, offer wireless capabilities built into their modem. This eliminates the need for a separate WLAN router.
In an office network environment, there usually is a network router in place already, so the addition of a WLAN router creates problems. In this case, there would be two devices trying to do the same job. For these types of networks, what the user will want is not a WLAN router but a WLAN access point. A WLAN router actually is a normal router with a WLAN access point built into it. A WLAN access point merely separates these two functions.
For computers that don’t have WLAN cards built into them, there are other options. A WLAN dongle can be purchased that plugs into a universal serial bus (USB) port that will make the computer wireless. For older laptops, there are WLAN cards that plug into card slots. For desktop computers, the WLAN USB device or a WLAN card can be installed.
Whether a WLAN router or a WLAN access point is used, security is a concern. Left unchecked, these devices can leave networks vulnerable to nearby hackers. For this reason, a security device known as a wired equivalent privacy (WEP) key was developed. This is a series of random letters and numbers that a device needs to have entered to be able to access the router or WLAN access point.