ZyXEL Communications MSC1000G Series, Руководство пользователя

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Chapter 11 Profile Screens
Management Switch Card User’s Guide
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PhyR Select enable to use the VDSL physical layer for data re-transmission when impulse noise
occurs. This helps to get better link connection quality.
Select disable to turn this feature off.
Select auto to have the system enable this feature when there is no impact to the data
rate.
G.inp Effective
Throughput Rate G.inp refers to settings for ITU-T G.988.4’s improved impulse noise protection.
Specify minimum and maximum allowed throughput rates in kbps.
G.inp Max Net
Data Rate Specify the maximum allowed net data rate in kbps.
G.inp SHINE Ratio A Single High Impulse Noise Event (SHINE) is non-periodical (random) electrical noise
encountered on DSL lines. They are usually large pulses that have a short duration.
Specify the assumed fraction of NDR to correct SHINE noise.
G.inp LEFTR
Threshold Specify the threshold for declaring a Low Error-Free Troughput Rate defect. This is a
percent of the net data rate.
G.inp Delay Specify the maximum and minimum allowed number of milliseconds of retransmission
delays. It is recommended that you configure the same delays for both upstream and
downstream.
G.inp Min INP Specify the minimum impulse noise protection (INP) against SHINE in units of 0.5 DMT
symbols.
G.inp Min INP for
REIN Specify the minimum impulse noise protection (INP) against Repetitive Electrical Impulse
Noise (REIN) in units of 0.5 DMT symbols.
This is the number of consecutive DMT symbols corrupted by REIN for which errors can be
completely corrected by the retransmission function, regardless of the number of errors
within the errored DMT symbols. A higher symbol value provides higher error correction
capability, but it causes overhead and higher delay which may impact multimedia data
receiving quality.
G.inp Frequency
for REIN REIN impulse noise is commonly caused by electrical power cables and thus repeats at a
rate of twice the AC power frequency (100 or 120 Hz). Select 5 for 100 Hz or 6 for 120
Hz.
G.inp
Retransmission
Mode This setting controls activation of retransmission during initialization.
disable : G.998.4 retransmission not allowed
prefer : have the system try to use G.998.4.
force : require the system to use G.inp. The CPE must also be set to support G.inp in the
same direction, otherwise initialization will fail.
test : require the system to use G.inp in test mode when triggered by the presence of
stationary noise. The CPE must also be set to support G.inp in the same direction,
otherwise initialization will fail.
SOS Min Rate Set the minimum bearer rate that must be guaranteed after an SOS in kbps. This allows a
large, emergency rate reduction to keep a connection up as long as possible.
Apply Click Apply to save the changes in this screen to the system’s volatile memory. The
system loses these changes if it is turned off or loses power, so use the Config Save link
on the navigation panel and then the Save button to save your changes to the non-
volatile memory when you are done configuring.
The new or modified entry then displays in the summary table below.
New While you are modifying a profile, you can click New to start configuring a fresh profile
without saving your changes.
Cancel Click Cancel to start configuring the screen again.
Index This is the number of a VDSL2 channel profile.
Table 166
Profile > VDSL2 > ChanProfile
LABEL DESCRIPTION