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Configuration: Basic Gateway TCP/IP Wireless Print Server USB

PPPPoint-to-Point Protocol is used to transport other protocols, typically for simple links over serial lines. It is most commonly used to access the Internet with a dial-up modem.

PPTP

Point-to-Point Tunneling Protocol encapsulates other protocols. It is a new technology to create VPNs

 

developed jointly by several vendors.

private IP

An IP address assigned to a computer on the SBG LAN by the DHCP server on the SBG for a

address

specified lease time. Private IP addresses are used by the SBG LAN only; they are invisible to devices

 

on the Internet. See also public IP address.

protocol

A formal set of rules and conventions for exchanging data. Different computer types (for example PC,

 

UNIX, or mainframe) can communicate if they support common protocols.

provisioning

The process of autodiscovery or manually configuring a cable modem on the CMTS.

PSTN

The public switched telephone network is the traditional circuit-switched, voice-oriented telephone

 

network. See also POTS.

public IP

The IP address assigned to the SBG by the cable service provider. A public IP address is visible to

address

devices on the Internet. See also private IP address.

Q

QAM

Quadrature Amplitude Modulation uses amplitude and phase modulation to encode multiple bits of

 

data in one signaling element. QAM achieves faster data transfer than amplitude or phase modulation

 

alone, but the signal is more prone to errors caused by noise. QAM requires a transmission circuit with

 

a higher CNR than alternate modulation formats such as QPSK. Two types of QAM are:

 

16 QAM encodes four bits per symbol as one of 16 possible amplitude and phase combinations.

 

64 QAM encodes six bits per symbol as one of 64 possible amplitude and phase combinations.

QPSK

Quadrature Phase Shift Key (QPSK) modulation sends two bits of information per symbol period with

 

one symbol 90 degrees out of phase with other symbols. The four constellation points represented by

 

the coordinates (0,0 - 0,1 - 1,0 - 1,1) represent the four possible combinations.

QoS

Quality of service describes the priority, delay, throughput, and bandwidth of a connection.

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SBG1000 Wireless Cable Modem Gateway User Guide

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Motorola SBG1000 manual 138, Pptp, Pstn, Qam, Qpsk