Network Interface Controller
A Network Interface Controller (NIC), also known as a network interface card, network adapter, LAN adapter, or physical network interface, is a computer hardware component that connects a computer to a computer network. It facilitates communication between devices on a network and provides an interface for computers to send and receive data over local area networks (LANs) or larger networks such as the Internet.
Types of Network Interface Controllers
Wired Network Interface Controllers
Traditionally, wired NICs utilize various technologies, with Ethernet being the most prevalent. Ethernet NICs range from Fast Ethernet, which supports data rates of 100 Mbit/s, to Gigabit Ethernet and 10 Gigabit Ethernet, providing higher throughput capabilities. Specialized NICs can support Power over Ethernet (PoE), supplying electrical power along with data over the same Ethernet cabling.
Wireless Network Interface Controllers
A Wireless Network Interface Controller (WNIC) connects to a wireless network via Wi-Fi, Bluetooth, or LTE. These WNICs enable devices to communicate over a network without the need for cabling, using radio frequency signals.
Virtual Network Interfaces
Virtual Network Interfaces are software-defined interfaces that operate within the operating system to manage network connections without relying directly on physical hardware. They are often used in virtual machines and cloud computing environments.
Functionality of Network Interface Controllers
NICs are responsible for translating data from the computer into a form suitable for transfer over the network. They handle the data link layer and physical layer specifications in network communications, such as framing and sending Ethernet frames, error checking, and data flow control. The integration of NICs into computers can be through either an expansion card or embedded directly on the motherboard.
Intelligent Platform Management Interface
Some NICs are part of systems supporting the Intelligent Platform Management Interface (IPMI), allowing remote management capabilities for servers by utilizing side-band connections. This solution is efficient for maintaining system health and managing server resources.
Networking Hardware and Interface Controllers
NICs are a vital component of networking hardware, working alongside other devices like network switches, routers, and modems to establish and manage network connections. NICs ensure that data is transmitted accurately and efficiently across the network.
The Role of NC-SI and MCTP in Network Interfaces
Network Controller Sideband Interface (NC-SI) is an electrical interface and protocol that allows for out-of-band communication, enhancing server management. The Management Component Transport Protocol (MCTP) is supported by some NICs to facilitate communication over protocols like PCI Express and SMBus.