Data Communication and Networking – Connecting LANs, Backbone Networks, and Virtual LANs Study Notes

A repeater is a connecting device that operates in the physical layer of the Internet model. A repeater regenerates a signal, connects segments of a LAN, and has no filtering capability.

A bridge is a connecting device that operates in the physical and data link layers of the Internet model.

A transparent bridge can forward and filter frames and automatically build its forwarding table.

A bridge can use the spanning tree algorithm to create a loopless topology.

A backbone LAN allows several LANs to be connected.

A backbone is usually a bus or a star.

A virtual local area network (VLAN) is configured by software, not by physical wiring.

Membership in a VLAN can be based on port numbers, MAC addresses, IP addresses, IP multicast addresses, or a combination of these features.

VLANs are cost- and time-efficient, can reduce network traffic, and provide an extra measure of security.