Configure legacy protocols Configure X.25 parameters
Digi TransPort WR Routers User Guide 553
X.25 LAPB parameters
LAPB (Link Access Procedure Balanced) is a standard subset of the High-Level Data Link Control
(HDLC) protocol. It is a bit-oriented, synchronous, link-layer protocol that provides data framing,
flow control and error detection and correction. LAPB is the link layer that X.25 applications use. On
Digi TransPort routers, you can use LAPB over ISDN or over a synchronous serial port.
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 need to
be changed.
To Next Page
Loading...
