This variable represents the loopback configuration of the DS3/E3
interface. Ther values mean:
ATM_DSX3_LOOPBACK_NONE : 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.
ATM_DSX3_LOOPBACK_PAYLOAD : 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.
ATM_DSX3_LOOPBACK_LINE : The received signal at this interface
does not go through the device
(minimum penetration) but is looped
back out.
ATM_DSX3_LOOPBACK_OTHER : Loopback's that are not defined here.