This variable represents the loopback configuration
of the DS3/E3 interface.
The values mean:
dsx3NoLoop
Not in the loopback state. A device that is
not capable of performing a loopback on
the interface shall always return this as
it's value.
dsx3PayloadLoop
The received signal at this interface is looped
through the device.
Typically the received signal
is looped back for retransmission after it has
passed through the device's framing function.
dsx3LineLoop
The received signal at this interface does not
go through the device (minimum penetration) but
is looped back out.
dsx3OtherLoop
Loopbacks that are not defined here.