Objective

Limiting a virtual number to accepting only one inbound call at a time.

Applies To

• Virtual Numbers
• Concurrent Calls

Procedure

Restricting the amount of concurrent calls per virtual number can depend on the inbound forwarding method you are using.

SIP

If you only wish to receive only one inbound call per virtual number, you should respond with a SIP response of 486 for any subsequent calls.

Voice API

If you are forwarding the call to different parties as a voice proxy to mask caller and recipient numbers, you will need to either handle the inbound calls and track whether the active outbound call has been completed and then serve the appropriate NCCO. If the user is busy, this may be a message stating the user is unavailable.

Alternatively, if you allow the calls to forward using a Connect action, the recipient user should ensure they have Call Waiting and Forward to Voicemail turned off, so that their network or operator will refuse the call as busy and the call will not be displayed on the recipient user's handset.

Forward to Phone

If you are forwarding using the Forward to Phone feature available on voice-enabled virtual numbers, the only way to avoid a second call being received is ensure the final recipient user has Call Waiting and Forward to Voicemail turned off, so that their network or operator will refuse the call as busy.