It would be great if there was a global variable to set an Alert-Info variable for internal calls to extensions.
in globals something like
INT_ALERTINFO=Internal
then when calls made to an extension from internal could use
SIPAddHeader(Alert-Info: <${INT_ALERTINFO}>)
this comes in handy for using a different ring on external calls versus internal.
it may be necessary to actually set the variable as a channel variable instead of a global now that i think about it. Perhaps calls that arrive from-external get ALERTINFO set to a defined value and calls that originate in from-internal get a different ALERTINFO value set.
Having a different ring for internal vs external is probably on the to 5 features requested by customers. The actual value of internal versus external could be defined in the general pbx option area of Thirdlane PBX.
What are the other four?