3Com 3C10402B, Руководство администратора

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LOSSARY
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LAN switch A network device that connects stations or LAN segments, also known as
a frame switch.
latency The sum of all the delays in an end-to-end connection.
layering The process of dividing complex software up into several layers, each of
which performs a specific task. Layering allows faster and easier software
development and is often used in public, open software.
LCD Liquid Crystal Display. A low cost display technology.
line pool In a PBX system, outside lines are pooled and arbitrated by the Call
Processor. To call an outside number, a user must dial the line pool access
number, typically 9, and the Call Processor assigns the next available line.
LLC Logical Link Control. A data link protocol for LANs that is part of the IEEE
802.2 standard and common to all LAN standards for OSI model data
link, level two transmissions.
loop start The most common signaling method in the public telephone network,
typically used for residence and business
CO lines.
M
MAC Media Access Control. A sub-layer of the Data Link layer (Layer 2) of the
ISO
OSI model responsible for media control. Also known as the “MAC
layer.”
MAC address A unique 48-bit number that is encoded in the circuitry of a device to
identify it on a LAN. Also known as a “hardware address” or an
“
Ethernet address.”
managed hub A network device in which each port on the hub can be configured,
monitored, and enabled or disabled by a network administrator from a
hub management console or utility tied into an SNMP (Signaling Network
Management Protocol) platform. Hub management can also include
gathering information about network parameters.
MAU Medium Attachment Unit. A transceiver that provides the correct
electrical or optical connection between the computer and IEEE 802.3
LAN media.
MIB Management Information Base. A database that can be accessed by a
gateway running CMIP (Common Management Information Protocol),