EXFO MAX-635G, User Manual

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Running DSL/IP Tests and Viewing Results
Copper and G.fast/VDSL2/ADSL2+ Multi-play Test Set
389
DSL Parameter Details

Parameter - Downstream / Upstream

Actual Data Rate
displays the values at which the unit and CO are
connected, as negotiated during the training phase. The values
should represent what the CO was set to, unless the DSL link is
being subjected to high levels of noise/crosstalk.

SNR
is the signal-to-noise ratio margin measured on the line.

Attenuation is line attenuation measured during the training
phase.
Note: DSL Param Details
displays
Attenuation
for ADSL1/2/2+ and G.fast.
See
Band Information
for VDSL2 attenuation.

Capacity is the capacity of the line as a ratio of achieved bit rate
over the maximum attainable bit rate presented as a percentage
(%). A high value could mean that the link is nearing its maximum
capabilities while a low value could mean the link is being under
utilized (sometimes intentionally – verify your local DSLAM setup).

Maximum Data Rate
displays the maximum attainable bit rates
that the circuit can handle as determined by the remote terminal
and CO during the training phase. Values can be greater than the
actual bit rate.

Output Power
is the current transmit power level that is a measure
of the aggregated transmit power.

Latency
is the path type,
Fast
or
Interleave
, set by the service
provider at the CO. The use of the interleaved path means greater
delay in the delivery of data but it is less susceptible to noise or
crosstalk due to increased Reed-Solomon coding and FEC
(forward error checking). The use of the fast path means little or
no delay in the delivery of data but it is more susceptible to noise
and crosstalk.