My Technical Notes

The template for the notification email is stored in the ${emailbody} variable, defined in voicemail.conf or one of its includes. You just have to define it. Feel free to mix in any of these system variables while you’re at it:

VM_NAME

The name of the subscriber for whom the message was [...]

Terminology Recap

POTS

Plain old telephone service, the basic analog phone line most folks have in their homes.

Fax

Facsimile, a method of sending a copy of a paper document over an analog telephone line.

Modem

Modulator/demodulator, a device that connects computer systems or fax machines by transmitting signals using analog signals.

CO

Central office, the [...]

Asterisk’s sip.conf file, in /etc/asterisk, contains entries for each SIP endpoint or trunk that can communicate with the Asterisk SIP server agent. Each entry can have multiple allow and disallow keywords, which indicate what codecs are to be used for each peer. The following configuration sets up a group of [...]

When you set up VoIP trunks from the Asterisk server to various providers, what you’re really doing is registering Asterisk as a VoIP client. To monitor the status of each trunk’s registration, use the sip show registry and iax2 show registry commands. Here’s a SIP trunk registration in progress:

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