5.5.3.6. Switching the Tie Trunk Circuits On and Off 
When switching off tie trunk circuits (analog or digital), the AMO
DSSU (regardless of the parameter OFFTYPE) leaves the line marking unchanged.
In contrast, when switching on or restarting a tie trunk circuit with
the following properties (regardless of the parameter ONTYPE), the line
marking is set for all configured B-channel groups:
- The tie trunk circuit must be assigned the CorNet-NQ protocol (AMO TDCSU, parameter PROTVAR))
- The CorNet-NQ protocol must be configured with Segmentation 8 (AMO TDCSU, parameter SEGMENT)
- The Polling Timer must be configured (AMO ZAND, parameter NWTOPTIM > 0)
This results in the automatic detection of the partner node being started faster when
the
feature is activated.
The AMO TDCSU, which likewise switches circuits off and on, acts in exactly the same
way as
described previously for the AMO DSSU.