Verilink NCC Craft Port -- KEEP ALIVE --
Keep Alive is a CSU function which is used to insure there will always be valid
T1 signals being sent out to the T1 network. T1 circuits require that pulses, which
represent ones, be sent at least once every so often in order to keep the equipment
in the T1 path synchronized at the same clock rate. In order to protect the T1 in cases
where the customer premise equipment is disconnected or malfunctioning
(to keep the T1 alive) the CSU will normally use one of the following methods.
net keep-alive (1)none (2)loop (3)ais (4)fais >
(1) - no Keep Alive signals will be sent. Verilink does not
recommend this choice
(2) - Loop Keep Alive means that the CSU will transmit the receive datastream back
to the T1. An advantage of this choice is that it will not create an alarm in most
DACS.
(3) - AIS stands for Alarm Indication Signal, it is a constant pattern of unframed
All Ones. This selection usually will create an alarm, it is used for that purpose,
to indicate that the local equipment has failed.
(4) - FAIS is Framed Alarm Indication Signal. While it will not alarm most DACS, the
pattern of All Ones in the 24 timeslots will tell a far end voice switch that the
T1 is not available.
The user is free to choose the desired value for this option.
Return to NCC Craft Tutorial