Configuration options on this page govern the analogue telephone line to the exchange. The dial plans outlined below will be invoked in the circumstance that someone dials into the unit, a timeout is set, and no-one answers the phone. We've not discussed how to setup that capability yet. Be mindful that if you don't pick up the phone, any inbound caller can get a new outbound dial tone on your phone.
If a PIN/Password has been specified for a particular gateway, then the person dialing in will be prompted with the password tone. Clearly the lack of a password/pin is a security risk. One must take care because one would not necassarily set a password for an account that has not been created. From the perspective of the SPA3102, the actual process of remote dialing a call, requires a dial plan such that the SPA3102 can choose the target route. Perhaps a way to think about this is that the creation of a dial plan that uses a gateway is equivalent to the more familiar practice of creating a user account. By denying the SPA3102 unused gateways, one also denies the opportunity for the SPA3102 to make the connection. The unit then seems to prevent the dial tone from appearing, on connections where a password is not specified.
The need for a default dial plan to be specified by the manufacturer seems strange for this unit, since PSTN caller could only be forwarded to VoIP and a VoIP caller to PSTN. This probably comes about because this small unit shares firmware with other bigger units, and the default settings were never localised. There is considerable flexibility here, but it is more than the unit is capable of, and then the default settings are not very secure.
None of this would be a problem if one could disable both the PSTN-To-VoIP and the VoIP-To-PSTN interfaces completely. As you may find if and when you experiment, the VoIP-To-PSTN Gateway Enable parameter must be set "Yes". Without this option it is impossible to dial out from the handset to the PSTN. From the perspective of the old analogue line your handset is now a VoIP caller.
Line Enable:
Yes
Dial Plans
Dial Plan 1-8:
(make empty)
This ensures that if the SPA3102 is accidentally left insecure, people will not be able to make calls charged to your phone bill
VoIP-To-PSTN Gateway Setup
VoIP-To-PSTN Gateway Enable:
Yes
PSTN-To-VoIP Gateway Setup
PSTN-To-VoIP Gateway Enable:
No
These remaining options are compatibility options specific to the UK. It is worthwhile to simply follow all of these closely simply to ensure a good quality integration of your SPA3102 with the exchange and telephone lines.