What Is A Network Interface Card?

Date First Published: 11th January 2024

Topic: Computer Systems

Subtopic: Computer Hardware

Article Type: Computer Terms & Definitions

Difficulty: Medium

Difficulty Level: 5/10

CONTENTS

Components
How Does A NIC Work?
Types Of NICs
Where Is The NIC Located?

Learn about what a network interface card is in this article.

A network interface card (NIC) is a hardware component that provides networking capabilities to a computer, allowing a computer to connect to a network. A NIC contains a socket on the card for a cable to connect to, providing the physical layer circuitry necessary for communicating with a data link layer standard, such as Ethernet or Wi-Fi. This provides a full network protocol stack, allowing communication among computers on the same local area network (LAN) and communications using routable protocols, such as IP.

The NIC allows computers to communicate over a computer network using cables or wirelessly. Since it provides physical access to a networking medium, the NIC is both a physical layer and a data link layer device.

Components

Although NICs work in the same way, they differ in terms of components, such as speed and MAC address. All NICs have a speed rating in terms of Mb/s that determines the performance of a card in a network, which on average comes in 10 Mb/s, 100 Mb/s, or 1000 Mb/s varieties. This is why it is best to match the specifications of a NIC to the standard of the network. A unique MAC address is also assigned to a NIC, which provides Ethernet packets to a computer.

How Does A NIC Work?

A NIC converts signals from cables or antennas into digital signals to send them over Ethernet cables, fibre optics or Wi-Fi waves. This process happens in real time without any manual action from either side. The signals are then decoded by devices on both sides of the connection for further processing.

Types Of NICs

Different types of NICs include:

Wired - NICs have input jacks made for cables, such as Ethernet.
Wireless - NICs use an antenna to provide a wireless connection using radio frequency waves.
USB - NICs can provide network connections through a device plugged into the USB port.
Fibre optics - Fibre optic NICs are more expensive and complex. Multiple NICs can be combined to achieve this support.

Where Is The NIC Located?

Most new computers have a NIC directly built into the motherboard due to the popularity and low cost of the Ethernet standard. In a desktop computer, the NIC is usually located near the USB ports at the back. In a laptop, the NIC is integrated into the motherboard and located on the side of the laptop. Users can purchase expansion card NICs if they need extra independent network connections.