is a small, simple, inexpensive device that joins multiple computers together. Many network hubs available today support the Ethernet standard. Other types including USB hubs also exist, but Ethernet is the type traditionally used in home networking.

is a device that gathers the signals from devices that are connected to it, and then regenerates a new copy of each signal.

is a device filters data traffic at a network boundary. Bridges reduce the amount of traffic on a LAN by dividing it into two segments.

are small physical devices that join multiple networks together.

is an internetworking system capable of joining together two networks that use different base protocols. A network gateway can be implemented completely in software, completely in hardware, or as a combination of both.

is a contraction of the terms modulator and demodulator. Modems perform a simple function: They translate digital signals from a computer into analog signals that can travel across conventional phone lines. The modem modulates the signal at the sending end and demodulates at the receiving end.

is a device that connects a client computer, server, printer orother component to your network. Most often, a network interface consists of a small electronic circuit board that is inserted into a slot inside a computer or printer. Alternatively, some computers, printers, or other services include network interfaces as part of their main circuit boards (motherboards).

protects a computer network from unauthorized access. Network firewalls may be hardware devices, software programs, or a combination of the two. Network firewalls guard an internal computer network (home, school, business intranet) against malicious access from the outside. Network firewalls may also be configured to limit access to the outside from internal users.