A network adapter can replace an internal network card when there is no card or when the internal card is not compliant with the required standard.
In a computer network, each machine must have a network card installed to communicate with the network router. The router directs traffic on the local network and also handles requests made to the Internet and subsequent responses.
The network card of each machine must support the same protocols as the network router so that all devices speak the same language.
There are two basic types of networks: wired and wireless. Network adapters are made for both types of networks, with more variety among the wireless types as there are different types of wireless networks.
A network adapter made for a wired connection is a small USB dongle that has an Ethernet port. Ethernet cabling connects computers on wired networks, with the RJ45 Ethernet port resembling a standard RJ11 phone jack on steroids.
The adapter may come bundled with software, although most modern operating systems will recognize a USB network adapter and apply the appropriate drivers when detecting the device.
Once recognized by the system, the external network adapter can be used to connect the computer to the network by running an Ethernet cable from the router to the network adapter.
In most cases, however, when people refer to a network adapter, they mean a wireless network adapter. These devices are popular for mobile computers as they allow the computer to connect to the home or office wireless network from anywhere nearby without being tethered by an Ethernet cable.
A wireless network adapter looks like a memory card or USB memory drive – a small USB key with an LED light that indicates power and operability.
When plugged in, it will scan radio waves for local transmissions, working with system software to display the names of local networks for the user.
Click the name of the network you want to join and provide the credentials as required. That’s all it takes to surf wirelessly. The next time you start up, the device will automatically connect you to the network of your choice.
Most laptops come with a built-in WiFi® card or wireless network card, but there are times when the supplied card does not work.
This is especially true when wireless standards are changing from one protocol to a newer and faster protocol. Older cards that only support the older protocol will not work with routers that only support the newer and faster standard.
At the time of this writing, the current wireless standard is 802.11n, which replaces the old 802.11g standard.
When the internal network card is not compatible with the desired standard, an alternative to an external adapter is to replace the internal card with a newer card. This is easy to do on a desktop computer, but not so easy on a laptop or notebook.
Simply accessing the card may involve more disassembly of the machine than many people are comfortable with. Also, opening a laptop can void the warranty. It is generally easier to opt for an external network adapter.
When buying a network adapter, there is little to consider except support for the desired protocols.
These handy little gadgets can be found almost everywhere, from local discount department stores to your favorite online retailers.