3com MSR 20-20 참조 매뉴얼

feac { detect | generate { ds3-los | ds3-ais | ds3-oof | ds3-idle | ds3-eqptfail | 
loopback { ds3-line | ds3-payload } } }

undo feac { detect | generate { ds3-los | ds3-ais | ds3-oof | ds3-idle | ds3-eqptfail | 
loopback { ds3-line | ds3-payload } } }

CT3 interface view

detect: Enables periodical far end and control signal (FEAC) channel signal 
detection. By default, periodical FEAC channel signal detection is enabled.

generate: Sends FEAC signals. Specify ds3-los for DS3 LOS, ds3-ais for DS3 AIS, 
ds3-oof for DS3 out of frame (OOF), ds3-idle for DS3 idle, and ds3-eqptfail for 
DS3 equipment failure. By default, FEAC signal sending is disabled.

loopback: Sends loopback code for activating far-end line loopback with the 
ds3-line keyword or payload loopback with the ds3-payload keyword. By 
default, loopback code sending is disabled.

Use the feac command to enable FEAC channel signal detection and sending on 
the CT3 interface.

Use the undo feac command to remove the current FEAC settings.

FEAC is a channel formed by using the third C-bit in the first subframe in C-bit 
framing. It is used to transmit alarm state signals for line test purpose or to 
transmit loopback control code for activating or deactivating far-end loopback 
during a loopback test.

According to ANSI T1.107a, the frame format used by FEAC channels is bit 
oriented protocol (BOP).

At the startup of your router, FEAC channel signal detection is enabled on the CT3 
interface with FEAC signal sending disabled.

After far-end loopback is activated with the feac generate loopback { ds3-line | 
ds3-payload } command, you may remove it with the undo form of the 
command.

n

You may view the transmitting/receiving state of the FEAC channel with the 
display controller t3 command.

Bits received (since latest sync) 

Number of bits received since the last synchronization

Table 21   Description on the fields of the display controller t3 command