Fluke 990DSL, Руководство пользователя

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990DSL
Users Guide
5-14
DSL Modem Test
The DSL Modem Test is a single-ended 990 Series II test that uses an external
Fluke Networks 990-GM/2 ADSL2+ or 990-GM/V VDSL2 “Golden Modem”
appliqué to test active ADSLx or VDSLx lines and equipment. Refer to the
990-GM/2 or 990-GM/V Quick Reference Guide for connection details.
You can set up the GM/2 to emulate the customer modem (RT emulation) for
any or all of 6 ADSLx Service Types. You can set up the GM/V to emulate
either the customer modem (RT Emulation) or the DSLAM (CO Emulation)
for any of 3 VDSLx Service Types.
When using the GM/2 (or GM/V in the RT Emulation mode) to test a
subscriber ADSLx (VDSLx) line in conjunction with a far end DSLAM, you
must disconnect the customer modem (CPE) from the line. When using the
GM/V in the CO Emulation mode to test a subscriber line in conjunction with
a far end customer modem, you must disconnect the DSLAM from the line.
The following description applies to usage of both the GM/2 and GM/V, as
their operation is generally the same. In either case, the DSL Modem Test will
control the GM via the 990’s serial port, and provide the following line
measurements after a successful connection:
Note
Test results that do not apply to a particular Setup configuration or
XDSL equipment configuration are identified by the following:“--“.
•
Attainable B/R
(Bit Rate, kb/s), Up & Down: Maximum net data rate
currently attainable on the facility under test, given its transmission
characteristics.
•
Actual B/R
(Interleaved or Non-interleaved), Channel 0 and Channel
1 (kb/s), Up & Down: Actual net data rate supplied to the customer
(Down) and to the DSLAM from the customer (Up).
If the channel is not interleaved (fast channel), the displayed title is
“Actual B/R”. If the channel is interleaved, the displayed title is
“Interleaved B/R”. The “Channel 1” field is provided for future
usage (results marked as “n/i”), where a secondary channel may be
configured for a different level of impulse noise protection than the
primary Channel (0).