Digi TransPort WR31 User Manual page 567

Configure legacy protocols
LCN direction
Whether the LCN for outgoing X.25 calls is incremented or decremented from the starting value
when multiple X.25 instances share one layer 2 (LAPB or LAPD), connection. The default is Down
and LCNs are decremented, such as if the first CALL uses 1024, the next will use 1023, etc.
Setting the parameter to Up causes the LCN to be incremented from the start value.
NUI/NUA selection
If both an NUI and an NUA are included in the call string, this parameter allows the router to filter
one of these out of the X.25 call request. This can be extremely useful in backup scenarios.
Consider the following example; the router is configured to do online authorizations via the ISDN
D channel and to fall back to B-channel (if the D-channel host did not respond for any reason).
Using this parameter in conjunction with the backup equivalent, it is possible to configure the
router to use the supplied NUA to connect over D-channel and the supplied NUI to connect over
B channel (for backup).
On the backup interface LCN
Sets the first LCN to use for the backup interface.
On the backup interface LCN Direction
Whether the LCN for the backup X.25 interface is incremented or decremented from the starting
value when multiple X.25 instances share a single layer 2 connection.
On the backup interface NUI/NUA selection
If both an NUI and an NUA are included in the call string, this parameter allows the router to filter
one of these out of the X.25 call request.
Enable X.25 Restart Packets
It is normally possible to make X.25 CALLs immediately following the initial SABM-UA exchange.
In some cases however, the X.25 network may require an X.25 Restart before it will accept X.25
CALLs. The correct mode to select depends upon the particular X.25 service to which you
subscribe. The default value is On. This means that the router will issue X.25 Restart packets. To
prevent the router from issuing Restart packets, set this parameter to Off.
Restart delay
When the Restarts parameter is On, the Restart delay value determines the length of time in
milliseconds that the router will wait before issuing a Restart packet. The default value is 2000
giving a delay of 2 seconds.
Digi TransPort WR Routers User Guide
Configure X.25 parameters
567