Agilent Technologies AuroraPresto, User Manual

Page: 159 / 266

Section 5 - ATM Layer Tests
Issue 7 - 05/02 4-59
The ADSL ATM BERT can be configured as follows:
• A single
Aurora Presto
with remote ATM PHY level
loopback.
Aurora Presto
generates the BERT Pattern
(transported in ATM cells) and the pattern is looped
back to the receiver. The BERT operates only on the
lower of the two ADSL line speeds (up to 800 Kbps
upstream speed). The ATM PHY or cell level loopback
must be invoked in the DSLAM (ATU-C) or in the
modem (ATU-R).
• Two
Aurora Presto
testers terminating the ends of the
ADSL line . This test runs a full bandwidth BERT at
upstream and downstream line speeds. You must set up
the testers to send and receive the same BERT pattern
at known line speeds over known VCCs (Virtual
Channel/Circuit Connections).
• A single
Aurora Presto
with
Aurora Jazz
connected
behind the DSLAM.
Aurora Presto
and
Aurora Jazz
are
used to generate ATM cells containing the BERT
pattern.
Note
The BERT pattern available on
Aurora Jazz
may be limited
by the software version installed.
Displaying ADSL physical layer BERT Results
See DSL Layer on page 4-33 .
Setting up an ATM BERT
Note
To be able to run an ATM BERT, you must set up the ADSL
layer to be connected.
-1-
From the
Select Test Mode
screen, press F4
Setup
to display the
Main Setup
screen.
-2-
Select
BERT
to display the
BERT Setup
screen.
481801-7.book Page 59 Thursday, May 23, 2002 10:46 AM