User`s guide

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LAPB X backup to interface
If any of the Switch from parameters has been set to LAPB X, and LAPB X is unavailable,
this parameter may be used to specify an alternative interface to switch the X.25 call to.
Any of the other interfaces may be chosen, or “None”. If “None” is chosen, then no backup
call will be attempted.
VXN backup to interface
If any of the Switch from parameters has been set to VXN, and VXN is unavailable, this
parameter may be used to specify an alternative interface to switch the X.25 call to. Any of
the other interfaces may be chosen, or “None”. If “None” is chosen, then no backup call will
be attempted.
LAPD Parameters
Calling Prefix
This parameter specifies 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 then 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 then it is removed from the calling NUA field.
D-Channel LCN
This is the value of the first LCN that will be assigned for outgoing X25 calls on LAPD.D-
Channel LCN Direction
Max VCs: Unlimited
This parameter sets the maximum number of Virtual Circuits (VCs) to be used on an LAPD
interface. When the maximum has been reached, then 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
This is 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
This is the default window size for calls being switched onto LAPD. The default window size
is 2, the valid range is 1 to 7.
LAPB Parameters
LCN
This is the value of the first LCN that will be assigned for outgoing X25 calls on LAPB.
LCN direction: Up Down
This parameter determines whether the LCN used for outgoing X.25 calls on LAPB is
incremented
or decremented from the starting value.
Max VCs: Unlimited
This parameter sets the maximum number of Virtual Circuits (VCs) to be used on an LAPB
interface. When the maximum has been reached, then 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.
B-Channel Number:
This parameter specifies an ISDN number to be used for calls being switched in the direction
of LAPB 0 or LAPB 1.