Introduction

Calls made in Voice broadcast and Call center campaigns terminate with multiple reasons either due to network failures or if the user is busy or invalid number formats. Typically the call failures are presented in the telecom terms and are often difficult to interpret.

This help document covers the common hangup causes and attempts to explain them in user-friendly language.

Hangup causes

• NORMAL_UNSPECIFIED - This cause is used to report a normal call event and the call is getting hung up after conversation. It indicates there is no error on the telecom side.
• UNALLOCATED_NUMBER - This cause indicates that the person called could not be reached because, either the number is not in a valid format, or the number is not currently allocated/assigned to anyone.
• NO_USER_RESPONSE - This is when the called person didn't respond to the call within the certain time limit (decided by the telecom operator, we don't have much control on it)
• UNKNOWN - Call failed at the carrier end for reasons not known to them
• NO_ANSWER - It's similar to no user response, but In NO_USER_RESPONSE, the telecom operator doesn't even get an acknowledgment if the called person was alerted of an incoming call. But in case of NO_ANSWER, the telecom operator knows the called person is alerted of the call but no one picks up.
• USER_BUSY - This cause is used to indicate that the called party is unable to accept another call because they are busy in another call.
• NORMAL_CLEARING - This cause indicates that the call is being cleared because the call is over for the right reasons like the conversation is complete.
• NORMAL_TEMPORARY_FAILURE - This cause indicates that the network is temporarily not functioning correctly for this VoIP call to establish correctly.
• CALL_REJECTED - This cause indicates the call is rejected by the person who was called.
• ORIGINATOR_CANCEL - This happens when the call is canceled by the person who made the call.
• INVALID_NUMBER_FORMAT - This cause indicates the number for the dialed call is not in a valid format.
• RECOVERY_ON_TIMER_EXPIRE - This cause is often associated with NAT problems and indicates the error handling procedure for the call has been initiated.
• INTERWORKING - This cause indicates that an interworking call (usually a call to SW56 service) has ended.