3Com MSR 50 Series, Руководство по настройке

Страница: 118 / 2443

118 C
HAPTER
4: WAN I
NTERFACE
C
ONFIGURATION
Starting/Stopping a
BERT Test on T1-F
Interface
BERT is operating as follows:
The local end sends out a pattern, which is to be looped over somewhere on the
line and back to the local end. The local end then checks the received pattern for
the bit error rate, and by so doing helps you determine whether the condition of
the line is good. To this end, you must configure loopback to allow the transmitted
pattern to loop back from somewhere on the line, for example, from the far-end
interface by placing the interface in far-end loopback.
You may view the state and result of the BERT test with the display ft1 serial
command.
Set the behavior of the
interface on the FDL in ESF
framing ft1 fdl { ansi | att | both |
none }
Optional
FDL is disabled by default.
Set the CRC mode crc { 16 | 32 | none } Optional
16-bit CRC by default.
Set the frame format ft1 frame-format { esf | sf } Optional
The default is esf .
Set alarm thresholds ft1 alarm-threshold los
pulse-detection
value
ft1 alarm-threshold los
pulse-recovery
value
ft1 alarm-threshold ais
{ level-1 | level-2 }
ft1 alarm-threshold lfa
{ level-1 | level-2 | level-3 |
level-4 }
Optional
For LOS alarm
The threshold of
pulse-detection defaults to
176 and the threshold of
pulse-recovery defaults to 22.
That is, if the number of the
pulses detected during the
total length of 176 pulse
detection intervals is smaller
than 22, the pulse-recovery
threshold, a LOS alarm occurs.
Both AIS alarm threshold and
LFA alarm threshold default to
level-1.
Set the type of line idle code ft1 idlecode { 7e | ff } Optional
The default is 0x7E.
Set the type of interframe
filling tag ft1 itf type { 7e | ff } Optional
The default is 0x7E.
Set the number of interframe
filling tags ft1 itf number number Optional
The default is 4.
Set the loopback mode ft1 loopback { local |
remote | payload }
Optional
Loopback is disabled by
default.
Send remote control loopback
code ft1 sendloopcode
{ fdl-ansi-llb-down |
fdl-ansi-llb-up |
fdl-ansi-plb-down |
fdl-ansi-plb-up |
fdl-att-plb-down |
fdl-att-plb-up |
inband-llb-down |
inband-llb-up }
Optional
No remote control code is
sent by default.
To do... Use the command... Remarks