Network Adapters for Home Networking - dummies

By Lawrence C. Miller

Computers and other devices require a network adapter (or network interface card, NIC) to connect to and communicate on a network. Most desktop and laptop computers sold today have a built-in network adapter. Look for an input jack on the back of your desktop computer (or on the back or side of your laptop computer) that looks similar to a telephone input jack, but slightly wider.

Many desktop and laptop computers also have a built-in modem. Don’t confuse the modem jack with the network jack. The network jack is slightly wider than the modem jack and will usually have two small LED lights in the top corners of the jack. You should also see a small telephone symbol near the modem jack and a small network symbol near the network jack.

A network jack (left) and modem jack (right) on the back of a laptop computer.
A network jack (left) and modem jack (right) on the back of a laptop computer.

Types of network adapters

If your computer doesn’t have a built-in network adapter or you need an additional one (if you’re building a computer-to-computer network without a hub or switch, for example), you have several options. Network adapters are fairly inexpensive and are available in a variety of forms, such as:

  • Desktop NIC (Network Interface Card): Installed in an empty PCI or PCI-E slot on your desktop computer’s motherboard. (This option requires you to open your computer case and is the most difficult to install.)

PCI (Peripheral Component Interconnect) and PCI-E (Peripheral Component Interconnect Express) are both computer expansion card standards. PCI-E is found on most new computers.

A desktop NIC.
A desktop NIC.
  • PC (or PCMCIA) Card: A card about the same size as a credit card (but much thicker) that you insert into the PC (or PCMCIA) Card slot of your desktop or laptop computer.

    PCMCIA Card was the original name for these types of cards. The abbreviation stands for Personal Computer Memory Card International Association. The name was later changed to PC Card, and they are now officially known as an ExpressCard. Most people still refer to all of them as PCMCIA cards though.

    A PC Card network adapter.
    A PC Card network adapter.
  • USB adapter: A small device with a USB interface, typically the size of a thumb drive, that you plug into the USB port of any computer or network device with a USB port.

    A USB network adapter.
    A USB network adapter.

Ethernet standards for home networking

Ethernet is a networking standard that helps to ensure that all computer networking technologies from different vendors can work together on a network. The standard was developed in 1980 by the IEEE (Institute of Electrical and Electronics Engineers) and is officially known as the 802.3 standard.

Supported Ethernet standards are listed in the specifications and datasheets of various networking hardware and on the product packaging. Here’s what to look for and what it all means:

  • 10BASE-T: Supports data rates up to 10 Mbps (megabits per second).

  • 100BASE-TX: Supports data rates up to 100 Mbps.

  • 1000BASE-T: Supports data rates up to 1000 Mbps (or 1 Gbps, gigabit per second).

If you think you’ve spotted a pattern here, you’re absolutely correct! The first number (10, 100, or 1000 in these examples) denotes the speed in Mbps. BASE indicates that the cable uses baseband signaling, in which a single signal is transmitted over a wire, as opposed to broadband signaling, in which many signals across a wide range of frequencies are transmitted over a channel (or wire). Finally, T or TX indicates that it uses twisted-pair cables.

Do not confuse megabytes (MB) and megabits (Mb). Megabytes describe the amount of disk storage or memory. Megabits are used to describe the speed of a network connection (including your Internet connection). While mega- means the same thing in both terms — that is, 1000 — a byte is equivalent to 8 bits. So a megabyte is 8 times larger than a megabit.