InterFAX uses multiple phone carriers (“routes”) for establishing calls to the fax destinations. The carriers are spread all over the world.
This feature ensures that every measure possible is automatically taken to successfully deliver the fax. Not all providers operate this way, and require manual intervention, and sometimes additional cost per call, to make repeat attempts.
When a fax is submitted, InterFAX will identify the list of possible routes for this particular fax call (the list may change from one call to the next - even if the same number was used). The first call attempt will be made from the route which has the highest chance of succeeding.
If the call fails, InterFAX will analyze the call failure to identify the type of error:
- Call placement failure: This error happens in case that the carrier used was not able to establish an outgoing call to the destination - for example, the carrier is restricted from making calls to that destination.
- Call connect failure: This error happens in case that the call failed when reaching the destination number - for example, the destination number is busy or there is no answer.
If there is a call placement failure, InterFAX assumes that the issue is with the carrier and will automatically reroute the fax to another route so that the next call attempt will be made from a different carrier.
InterFAX will also record the call placement failure in a log and for the next 24 hours, InterFAX will not use this route for faxes to this number again.
If there is a call connect failure, InterFAX assumes that the issue is temporary with the recipient, and the carrier used is capable of establishing the call in the future. The next call attempt will take place through the same route after the interval set by the user.
InterFAX will go through all available routes and all call attempts specified by the user until the fax is either sent successfully or no further attempts are left remaining.