Digi TransPort WR11 User Manual page 667

Configuring legacy protocols
VXN backup to interface
If any of the Switch from parameters has been set to VXN, and VXN is unavailable, you can use
this parameter to specify an alternative interface to switch the X.25 call to. Any of the other
interfaces may be selected, or None. If None is selected, no backup call is attempted.
3. Configure LAPD parameters:
Calling Prefix
The call prefix to inserted in front of the NUA in calls being switched to LAPD. For example, if
the called NUA in the call being received by the LAPB 0 interface is 56565, and the call prefix is
0242, the call placed on the LAPD interface is to NUA 024256565. Also, for calls in the reverse
direction, if the prefix in the calling NUA matches this parameter, it is removed from the calling
NUA field.
D-Channel LCN
The value of the first LCN assigned for outgoing X25 calls on LAPD.D-Channel LCN Direction.
Max VCs: Unlimited
The maximum number of Virtual Circuits (VCs) on an LAPD interface. When the maximum has
been reached, the backup call will take place immediately, or the call will clear if there is no
backup call. If this parameter is set to 0, there is no limit.
Default Packet Size
The default packet size for X.25 calls being switched onto LAPD. The default packet size is 128,
other possible values are 256, 512, or 1024 bytes.
Default Window Size
The default window size for calls being switched onto LAPD. The default window size is 2; the
valid range is 1 to 7.
4. Configure LAPB parameters:
LCN
The value of the first LCN that will be assigned for outgoing X25 calls on LAPB.
LCN direction: Up Down
Determines whether the LCN for outgoing X.25 calls on LAPB is incremented or decremented
from the starting value.
Max VCs: Unlimited
The maximum number of Virtual Circuits (VCs) on a LAPB interface. When the maximum has
been reached, then the backup call occurs immediately, or the call will clear if there is no
backup call. If this parameter is set to 0, there is no limit.
B-Channel Number
An ISDN number for calls switched in the direction of LAPB 0 or LAPB 1.
Enable ENQ Char
When this parameter is set to On, when an incoming call on LAPB is switched and the router
connects to it, the X.25 switch sends a data packet on the LAPB X.25 SVC containing the ENQ
character.
Digi TransPort® Routers User Guide
Configure Protocol Switch software
667