Digi TransPort WR31 User Manual page 556

Configure legacy protocols
Mux mode
Controls the multiplexing mode.
DLC #
The data link channel number to use for this virtual ASY port.
ASY port
The physical ASY port over which to multiplex.
Virtual ASY port
The virtual ASY port number that this LAPB instance will multiplex over the physical port.
Digi TransPort WR Routers User Guide
Configure X.25 parameters
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