Digi TransPort User Manual page 334

X.25 parameters
Use: Serial port Port x (in Synchronous Mode)
To use the LAPB instance over a synchronous serial port enable this setting and select a serial
port number. To configure settings of the synchronous port such as speed and clock source
navigate to Configuration - Network > Interfaces > Serial > Serial Port n > Sync Port n.
Use: ISDN
Enable this setting to use LAPB over ISDN.
Mode DTE or DCE
Determines whether LAPB will behave as DTE (Data Terminal Equipment) or DCE (Data Circuit-
terminating Equipment) in an X.25 protocol sense. (Physical DTE vs. DCE wiring cannot be
changed by configuration.)
N400 Counter x
This is the standard LAPB retry counter. The default value is 3 and it should not normally be
necessary to change this.
RR Timer x milliseconds
This is a standard LAPB "Receiver Ready" timer. The default value is 10,000ms (10 seconds)
and it should not normally be necessary to change this.
T1 Timer x milliseconds
This is a standard LAPB timer. The default value is 1000 milliseconds (1 second) and under
normal circumstances, it should not be necessary to change it.
Digi TransPort User Guide 334