L
Glossary
LAN
Local Area Network. A computer network that spans a relatively small area. Most LANs are confined to a single building or group of buildings. However, one LAN can be connected to other LANs over any distance via telephone lines and radio waves. A system of LANs connected in this way is called a
Most LANs connect workstations and personal computers. Each node (individual computer) in a LAN has its own CPU with which it executes programs, but it also is able to access data and devices anywhere on the LAN. This means that many users can share expensive devices, such as laser printers, as well as data. Users can also use the LAN to communicate with each other, by sending
There are many different types of LANs, Ethernets being the most common for PCs. Most Apple Macintosh networks are based on Apple's AppleTalk network system, which is built into Macintosh computers. The following characteristics differentiate one LAN from another:
topology: The geometric arrangement of devices on the network. For example, devices can be arranged in a ring or in a straight line.
protocols: The rules and encoding specifications for sending data. The protocols also determine whether the network uses a
media: Devices can be connected by
LANs are capable of transmitting data at very fast rates, much faster than data can be transmitted over a telephone line. However, the distances are limited and there is also a limit on the number of computers that can be attached to a single LAN.
lock
A state that prohibits other users from accessing a resource, such as a device or interface.
logical unit
A logical unit is a number associated with an interface. In Agilent SICL, a logical unit uniquely identifies an interface. Each interface on the controller must have a unique logical unit.
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