284 CHAPTER 17: FUNDAMENTAL CT3 INTERFACE CONFIGURATION COMMANDS
View CT3 interface view
Parameter line-number: T1 line number, in the range 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.
Description Use the t1 set fdl command to set the behavior of the specified T1 line on the
FDL in ESF framing.
Use the undo t1 set fdl command to disable FDL of T1.
By default, FDL is disabled.
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.
These two commands only apply to channelized T1 lines with their T1 frame
format being ESF.
Example # Set the FDL to be ANSI T1.403 compliant for T1 line 1 on CT3 interface T3 2/0.
<Sysname> system-view
[Sysname] interface t3 2/0
[Sysname-T3 2/0] t1 1 set fdl ansi
t1 show
Syntax t1 line-number show
View CT3 interface view
Parameter line-number: T1 line number, in the range 1 to 28.
show: Displays the physical line state of the specified T1 line.
Description Use the t1 show command to have a quick look at the line state of the specified
T1 line on the CT3 interface.