Which of the following is not a network device?

The network device that is not a network device is "Port". A port is not a network device; it is a connection point or a socket on a network device such as a switch, hub, or router. A hub is a network device that connects multiple devices together to form a network, and it is responsible for transmitting data to all the devices connected to it. A modem is a device that connects a computer or network to the internet or other wide-area networks by converting digital signals into analog signals that can be transmitted over telephone lines or cable lines. A router is a network device that forwards data packets between computer networks, allowing devices on different networks to communicate with each other. It determines the best path for data transmission and ensures that data is sent to the correct destination. In summary, a port is not a network device, but a connection point on a network device that allows devices to communicate with each other.