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4 atm qos, 5 traffic shaping, 4 atm qos 14.5 traffic shaping – ZyXEL Communications IES-708-22A User Manual

Page 119

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Chapter 14 xDSL Profiles Setup

IES-708-22A User’s Guide

119

14.4 ATM QoS

ATM Quality of Service (QoS) mechanisms provide the best service on a per-flow guarantee.
ATM network infrastructure was designed to provide QoS. It uses fixed cell sizes and built-in
traffic management (see

Section 14.5 on page 119

). This allows you to fine-tune the levels of

services on the priority of the traffic flow.

14.5 Traffic Shaping

Traffic shaping is an agreement between the carrier and the subscriber to regulate the average
rate and fluctuations of data transmission over an ATM network. This agreement helps
eliminate congestion, which is important for transmission of real time data such as audio and
video connections.

Min Rate

Type the minimum upstream transfer rate for this profile.

Annex Mode

Select the region setting.
Select annex_a to use DSL over POTS (G.992.1 Annex A).
Select annex_b to use DSL over ISDN (G.992.1 Annex B).

Wire Pair

Select a wire pair number.
Select 2wire for a normal connection using a single SHDSL port’s two wires,

this is the default.
Select 4wire for a 4-wire n-wire group (two SHDSL ports grouped together).
Select mpair4 for an 8-wire n-wire group (four SHDSL ports grouped together).

Line Probing Enable

Mode

The IES-708-22A and subscriber modem use line probes to determine the best

possible transmission rate. This is used in rate adaptation.
Select lp_off to have the IES-708-22A skip the rate adaptation phase to shorten

connection set up time.
Select lp_on_cur to enable line probing using the current target Signal to Noise

Ratio margin.
Select lp_on_wc to enable line probing using the worst case target Signal to

Noise Ratio margin.

Current Condition

SNR Margin

Type the current condition target Signal to Noise Ratio margin, -10 ~ 21 in dB.

Worst Case SNR

Margin

Type the worst case Signal to Noise Ratio margin, -10 ~ 21 in dB.

Add

Click Add to save your changes to the IES-708-22A’s volatile memory. The IES-

708-22A loses these changes if it is turned off or loses power, so use the Config

Save link on the navigation panel to save your changes to the non-volatile

memory when you are done configuring.

Cancel Click

Cancel to start configuring the screen again.

Table 24 Basic Setting > xDSL Profiles Setup (continued)

LABEL

DESCRIPTION