For the last five years, it has been possible to initiate outgoing calls via Voximplant cloud without specifying a source phone number. Such feature was provided mainly for new developers, and if an optional caller id was not specified, the special “fallback” number was used automatically. However, the telecom landscape has changed so far, and now many telecom operators drop such calls, which results in unwanted side-effects for the “call without a caller id” feature.

Starting on April 25 we change our callPSTN API: “caller id” is no longer optional and must be specified in your JavaScript source code for scenarios. You can use following phone numbers as a callPSTN caller id:

  • Phone numbers rented from Voximplant;
  • Phone numbers confirmed via the Voximplant control panel;
  • Incoming call phone number, if a JavaScript session has an incoming call;

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