NIC or Network Interface Card is a circuit board or expansion card or a chip, that enables a computer to connect to a network, be it a home network, or the Internet using an Ethernet cable. Initially, network controllers were implemented as expansion cards that could be plugged into a computer port, router or USB device. However, due to the popularity and low cost , nearly all modern computers have a built-in network interface in the motherboard. In case additional independent network connections are needed, expansion card NICs can be purchased and used.
A NIC implements a physical layer circuit, that is necessary to communicate with a data link layer standard (like Ethernet or Wi-Fi) . Thus it provides a computer with a dedicated, full time connection to a network.
Modern NICs expand the functionality of the system by providing – support for I/O Interrupt, Direct Memory Access interfaces, data transmission, network traffic engineering etc.
Types of Network Interface Cards (NICs)
Though NIC is a hardware which provides an interface between a computer and a network , there are multiple ways this connection can occur:
- Wireless – NICs that use an antennato provide wireless reception through radio frequencywaves. Wireless NICs are designed for Wi-Fi connection.
- Wired – NICs that have input jacks made for cables. Wired NICs are used for Ethernet Networks (wired LAN technology).
- USB – NICs that provide network connections through a device plugged into the USB port. These are not actually cards but instead regular USB devices that enable network connections through the USB port. These are called Network Adapters.
- Fiber Optic – These are modern, more complex and expensive NICs that are used as a high-speed support system for network traffic handling on server computers.