Understanding the different call statuses

Call Status	Definition	Remarks
Completed	Call is answered	You will also find a positive integer for the call duration and this call will be charged
Completed with Failure	Call is answered but some error occured	You will also find a positive integer for the call duration but the call was ended due to some failure on the network
No Answer or Not Answered	Call was not answered despite ringing	No call duration will be present.
Busy	Call was declined by the receiver	No call duration will be present.
Rejected or Cancelled	Call was cancelled by Unifonic	This could be due to some business rules on security policy or acceptable term of use. i.e. call was made outside of business hours
Failed	Call was not attempted by the operator	This could be due to the following reasons: i. invalid e.164 string ii. unreachable recipient iii. network error iv. network congestion v. inaccurate call status submitted by operator (more common for international calls)
Queued	Call is being processed	This could be due to congestion on the network due to insufficient or unavailable sip channels