R2511-HP MSR Router Series Interface Command Reference(V5)

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Usage guidelines
When a CT3 interface is operating in channelized mode, its T1 lines might use separate clocks.
Examples
# Use the internal clock as the clock source on the first T1 line on interface T3 2/0.
<Sysname> system-view
[Sysname] controller t3 2/0
[Sysname-T3 2/0] t1 1 set clock slave
t1 set fdl
Use t1 set fdl to set the behavior of the specified T1 line on the FDL in ESF framing.
Use undo t1 set fdl to disable FDL of T1.
Syntax
t1 line-number set fdl { ansi | att | both | none}
undo t1 line-number set fdl
Default
FDL is disabled.
Views
CT3 interface view
Default command level
2: System level
Parameters
line-number: T1 line number in the range of 1 to 28.
fdl: Sets the FDL format of T1.
ansi: Adopts ANSI T1.403 for FDL.
att: Adopts AT&T TR 54016 for FDL.
both: Adopts both ANSI T1.403 and AT&T TR 54016 for FDL.
none: Disables the use of FDL on the T1 line.
Usage guidelines
FDL is an embedded 4 kbps overhead channel within the ESF format for transmitting periodical
performance report (PPR) statistics or loopback code.
According to ANSI T1.403, the format of PPR is LAPD, and the format of loopback code is BOP.
The t1 set fdl command only starts PPR transmission. It cannot enable loopback code transmission or
detection.
This command only applies to channelized T1 lines with a T1 frame format of ESF.
Examples
# Set the FDL to be ANSI T1.403 compliant for T1 line 1 on CT3 interface T3 2/0.
<Sysname> system-view
[Sysname] controller t3 2/0