In order to set-up routing to PSTN, complete these steps:
Setting-up the Routing to PSTN
The SPA9000 has dial plan settings both for incoming and outgoing calls. For incoming, Contact List is being used. Since the SPA400 will be registered to one of the Lines of the SPA9000, use the Contact List to control the incoming calls. You can go to this link for reference:
Step 1: If the caller is one of the extensions registered to the SPA9000, change the Call Routing Rule under the SIP tab. This will control the outgoing calls.
Note: The default dial plan is "(<:L1,2,3,4>9xx.)".
Step 2: Look for Call Routing Rule then type "(<:L1>9xx.|<:L2>8xx.|<:L3>7xx. |<:L4>6xx.)" in the field.
Note: The above dial plan means that if the caller (phone registered to SPA9000) dials 9XXXXXX, SPA9000 uses Line 1, in case this line is registered to an ITSP, the caller can do an outgoing VoIP call. If the caller dials 8XXXXXX, SPA9000 uses Line 2 which is registered to the SPA400, allowing you to do an outgoing PSTN call.
Step 3: The Dial Plan of each line needs to be change. You will also have to change the dial plan of each line into something like this:
Line 1: (<9:>xx.)
Line 2: (<8:>xx.) Line 3: (<7:>xx.) Line 4: (<6:>xx.)