PRELIMINARYAppendix D: Glossary

margin

 

The noise margin in decibels that the modem must achieve with a BER of 10 -7or

 

 

better to successfully complete initialization.

 

MIB

 

Management Information Base is a set of variables that define the configuration and

 

 

 

 

RY

 

 

status parameters for network management. Network management stations can

 

 

retrieve information from and write information to an MIB. The Internet Engineering

 

 

Task Force (IETF) specifies standard MIBS for certain types of devices, ensuring any

 

 

NMS can manage the devices. Vendors can specify proprietary MIBs for their devices

 

 

to fit specific needs.

 

 

NAT

 

Network Address Translation provides the means to map private IP addresses to the

 

 

public IP addresses (proxy addresses) that are set up for the PPP sessions. Used with

 

 

PPP Mode. NAPT is Network Address and Port Translation.

NVRAM

 

 

 

A

 

Non-Volatile Random Access Memory is a medium for storing system configuration

 

 

information, so the information is not lost when the system is reset.

octet

 

 

N

 

 

A TCP/IP term indicating eight bits.

 

PAP/CHAP

Password Authentication Protocol and Challenge Handshake Authentication Protocol

 

 

are two ways to authenticate PPP sessions. With PAP, the modem sends

 

 

authentication requests to the service provider and authentication occurs only once

 

 

during the life of the link.

 

 

 

 

M

 

 

 

 

In CHAP, the service provider returns an authentication challenge to the modem

 

 

during authentication. CHAPIcan be renegotiated during the life of the link. Also, both

 

 

the modem and the service provider must support clear text versions of the

 

 

I

 

 

 

 

password. The CHAP host field must be the same on both ends of the session.

PDU

 

Protocol Data Unit is data as it appears at the interface between a particular sublayer

 

 

and the sublayer immediately below.

 

POTS

 

Plain Old Telephone Service.

 

 

PPP

 

Point-to-Point Protocol exists between the hardware layer and the network-layer

 

 

interface protocols. It is a widely used protocol for establishing connections on the

PR

Internet. PPP provides the set up and release of connections for each session.

PAP/CHAP provide the authentication for the PPP sessions.

 

 

proxy IP address

The proxy IP address is the WAN IP address for one of the 32 sessions. The proxy

 

ELIP address is used to enter static NAT entries. See IP address.

PVC

 

Permanent Virtual Circuit is a logical connection comprised of a predefined static

 

 

route across a packet-switched network that is always in place and always available.

QoS

 

Quality of Service is the configured traffic parameters that are assigned to a virtual

 

 

circuit, which specifies how quickly and how accurately data is transferred from the

 

 

sender to the receiver.

 

 

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