Linksys ATA Administration Guide
85
Call Scenarios
Configuring the PSTN (FXO) Gateway
Call Forwarding to PSTN Gateway
This section describes a number of scenarios that forward calls to the PSTN gateway. It includes
the following topics:
•
”Forward-On-No-Answer to the PSTN Gateway” section on page 85
•
”Forward-All to the PSTN gateway” section on page 85
•
”Forward to a Particular PSTN Number” section on page 85
•
”Forward-On-Busy to PSTN Gateway or Number” section on page 85
Forward-On-No-Answer to the PSTN Gateway
In this scenario, Line 1 is configured to
Cfwd No Ans Dest
to the PSTN Gateway. The scenario is
implemented by setting User 1 to forward to gw0 on no answer, with
Cfwd No Ans Delay
set to
six seconds.
The caller calls Line 1 and if Line 1 is not picked up after six seconds, the PSTN Line picks up the
call and the call reverts to a PSTN-Gateway call, as described above. In this case, HTTP
authentication is not allowed because Line 1 does not authenticate inbound INVITE requests. If
you need to authenticate the VoIP caller in this case, you must select the PIN authentication
method, or else the caller is
not
authenticated.
NOTE:
If the PSTN Line is busy at the moment of the forward, it does not answer the VoIP call.
The call forward rule is ignored and Line 1 continues to ring.
Forward-All to the PSTN gateway
In this scenario, Line 1 is configured with
Cfwd All Dest
parameter to the PSTN gateway.This
scenario is the same the previous case, except the FXO picks up the Line 1 call immediately.
If the PSTN Line is busy at the moment of the call, the PSTN Line does not pick up the call, the
call forward rule is ignored, and Line 1 continues to ring.
Forward to a Particular PSTN Number
In this scenario, the forward destination is set to <
target-number>@gw0
>. This is the same as in
the previous examples, except that the Linksys ATA device automatically dials the given target
number on the PSTN line right after it answers the VoIP call leg. This is a special case of one-
stage dialing where the target number is specified in the configuration. The caller is not
authenticated in this case regardless of the authentication method. However, the caller is still
limited by the
VoIP Caller ID Pattern
parameter
Forward-On-Busy to PSTN Gateway or Number
This scenario is similar to the previous cases of call forwarding to gw0, but this applies when
Line 1 is active.