Cisco 675 - 675 Router, Инструкция по установке и эксплуатации

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Glossary
8
Cisco 600 Series Installation and Operation Guide
78-11190-01
Permanent Virtual
Connection (PVC)
A fixed virtual circuit between two users: the public data network equivalent of
a leased line. No call setup or clearing procedures are needed.
physical layer
Handles transmission of raw bits over a communication channel. The physical
layer deals with mechanical, electrical, and procedural interfaces.
physical port
A physical connection to a computer through which data flows. An “Ethernet
port,” for example, is where Ethernet network cabling plugs in to a computer.
port
The abstraction used by Internet transport protocols to distinguish among
multiple simultaneous connections to a single destination host. See selector.
POTS
Plain Old Telephone Service. This is the term used to describe basic telephone
service.
PPP
Point-to-Point-Protocol. The successor to SLIP, PPP provides router-to-router
and host-to-network connections over both synchronous and asynchronous
circuits. See SLIP.
protocol
A formal description of messages to be exchanged and rules to be followed for
two or more systems to exchange information.
PVC
See Permanent Virtual Connection.
R
RADIUS
Remote Authentication Dial-In User Service (RADIUS). A client/server security
protocol created by Livingston Enterprises. Security information is stored in a
central location, known as the RADIUS server.
RADIUS
Accounting Client
Permits system administrators to track dial-in use.
RADIUS Security
Client
Controls access to specific services on the network.
P