R0106-HP MSR Router Series Interface Command Reference(V7)

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Usage guidelines
The maximum downlink rate might not reach the specified rate as restricted by the CO equipment and
line conditions. If you select the auto mode, CPE and CO can negotiate a rate commensurate with the
current line condition during the activation process. If fixed rates are set at both ends, the two parties
negotiate a rate. If the lower rate of the two cannot be provided, the line cannot be activated.
• For four-wire (dual-pair) G.SHDSL interfaces, the interface rate is two times higher than the
single-pair rate. For example, if you set the single-pair rate to 2312 kbps, the four-wire interface rate
is 4624 kbps.
• Because four-wire G.SHDSL interfaces cannot negotiate a rate, do not specify the auto mode for
them.
Examples
# Set ATM 1/0 to operate in the auto-negotiation mode.
<Sysname> system-view
[Sysname] interface atm 1/0
[Sysname-ATM1/0] shdsl rate auto
shdsl snr-margin
Use shdsl snr-margin to set a margin to signal-to-noise ratio (SNR).
Use undo shdsl snr-margin to restore the default.
Syntax
shdsl snr-margin [ current current-margin-value ] [ snext snext-margin-value ]
undo shdsl snr-margin
Default
Current-margin-value is 2 and snext-margin-value is 0.
Views
ATM SHDSL_4WIRE interface view, ATM SHDSL_8WIRE_BIS interface view
Predefined user roles
network-admin
Parameters
current current-margin-value: Specifies the target margin for the current SNR, in the range of 0 to 10. The
default value is 2. During SHDSL line training, this target margin is considered in addition to the current
SNR threshold. A larger margin value results in increased link stability and enhanced noise suppression
ability.
snext snext-margin-value: Specifies the target margin for the lowest SNR, in the range of 0 to 10. The
default value is 0. During SHDSL line training, this target margin is considered in addition to the lowest
SNR threshold. A larger margin value results in increased link stability and enhanced noise suppression
ability.
Usage guidelines
Setting the margin can affect the maximum rate of the line. When the line condition is good, you can set
a small margin to obtain higher rates. When the line is noisy, this might cause disconnections.