1.1 Recognize the purpose and functions of various network devices such as routers, switches, bridges and hubs
Routers are OSI model Network Layer 3 switches that interconnect networks over local or wide areas and provide traffic control and filtering functions when more than one pathway exists between two end-points on the network. Some routers have the capability to connect networks with different physical media and translate between different network architectures.
A network switch or switching hub is a computer networking device that connects network segments or network devices. The term commonly refers to a multi-port network bridge that processes and routes data at the Data Link Layer (Layer 2) of the OSI model.
A network bridge connects multiple network segments at the Data Link Layer (Layer 2) of the OSI model. In Ethernet networks, the term bridge formally means a device that behaves according to the IEEE 802.1D standard. A bridge and a switch are very much alike; a switch being a bridge with numerous ports. Switch or Layer 2 switch is often used interchangeably with bridge.
A hub is a central concentration point for the attachment of wires from workstations in a network. A passive hub is no more than a connection point, possibly a wiring panel or punchdown block that offers no amplification of the signal, while an active hub is powered and will regenerate signals from one device to another. Commonly referred to as a "dumb repeater", communications received by a hub through one port are sent out, or repeated, to every other available port on the hub. Typically used in a star network topology, hubs operate at the Physical Layer (Layer 1) of the OSI model.
|
