You identiﬁed network communications technologies. To complete your understanding of network concepts, you will need to examine the technologies that connect multiple nodes and networks together.
Deﬁnition: A Local Area Network (LAN) is a self-contained network that spans a small area, such as a single building, ﬂoor, or room. In a LAN, all parts of the network are directly connected with cables or short-range wireless media.
Figure: LANs within a building.
Premise wiring is a method for installing network cable and other components within building spaces to organize and protect the cables and components. There are several components in a premise wiring scheme.
Premise Wiring Component and Description
The wire that runs to a PC, printer, or other device connected to the network.
A connection point for drop and patch cables. Typically, a patch panel has one or more rows of RJ45 or other connectors. Drop cables are connected to the connectors. Cables run between the connectors to connect drop cables as needed.
Usually, a cable that is plugged into the patch panel to connect a drop to a concentrator device. A patch cable might or might not be a crossover cable, one in which the transmit conductor at one end is connected to the receive conductor at the other.
Individual wires that connect two drops at a patch panel. Cross connects are rarely used in modern networks. However, they are still frequently used with telephone wiring.
An Ethernet cable in which the transmit conductors at each end are connected to the receive connectors at the other. These can be used to connect similar devices (i.e., computer-to-computer or switch-to-switch), although the advent of Automatic Medium- Dependent Interface Crossover (Auto-MDIX) technology has made them all but obsolete.
A small room in which patch panels are installed. Drop cables radiate out from the wiring closet to the components on the net- work.
Deﬁnition: A Wide Area Network (WAN) is a network that spans multiple geographic locations. WANs typically connect multiple LANs using long-range transmission media.
Figure: A WAN.
Other Network Coverage Areas
Besides LANs and WANs, there are several other loosely deﬁned network categories, named according to the geographic areas they cover. These include:
- A personal area network (PAN), which is a network of devices used by a single individual, such as a user’s cellular phone with a wireless hands-free earpiece.
- A campus area network (CAN), which covers an area equivalent to an academic campus or business park. A CAN is typically owned or used exclusively by one company, school, or organization.
- A metropolitan area network (MAN), which covers an area equivalent to a city or other municipality.
- A global area network (GAN), which is any worldwide network.