Types of Networking Components and Devices
Modems
Standard telephone lines can transmit only analogue signals.
Repeaters
The purpose of a repeater is to extend the maximum range for the network cabling.
Bridges
Bridges extend the maximum size of a network.
Brouters
A brouter is a router that also can act as a bridge.
Gateways
Gateways connect dissimilar environments by removing the layered protocol information of incoming packets and replacing it with the packet information necessary for the dissimilar environment.
Modems
Standard telephone lines can transmit only analogue signals.
Computers, however, store and transmit data digitally.
Modems can transmit digital computer signals over telephone lines by converting them to analogue form.
Converting one signal form to another (digital to analogue in this case) is called modulation.
Recovering the original signal is called demodulation.
The word "modem" derives from the terms modulation/demodulation.
Modems can be used to connect computer devices or entire networks that are at distant locations.
Repeaters
The purpose of a repeater is to extend the maximum range for the network cabling.
A repeater is a network device that repeats a signal from one port onto the other ports to which it is connected.
A repeater passes on all signals that it receives.
Hubs
Hubs, also called wiring concentrators, provide a central attachment point for network cabling.
Hubs
Hubs, also called wiring concentrators, provide a central attachment point for network cabling.
Bridges
Bridges extend the maximum size of a network.
A repeater passes on all signals that it receives, while, a bridge is more selective and passes only those signals targeted for a computer on the other side.
A bridge can make this determination because each device on the network is identified by a unique physical address.
Each packet that is transmitted bears the address of the device to which it should be delivered.
Routers
Internetwork connectivity devices, such as routers, can use network address information to assist in the efficient delivery of messages.
Internetwork connectivity devices, such as routers, can use network address information to assist in the efficient delivery of messages.
Delivering packets according to logical network address information is called routing.
The common feature that unites internetwork connectivity devices (routers and brouters) is that these devices can perform routing
Brouters
A brouter is a router that also can act as a bridge.
A brouter attempts to deliver packets based on network protocol information, but if a particular Network layer protocol isn't supported, the brouter bridges the packet using device addresses.
Gateways
Gateways connect dissimilar environments by removing the layered protocol information of incoming packets and replacing it with the packet information necessary for the dissimilar environment.
