RETURNED TO THE CALLER. You have canceled the call invitation.
RETURNED TO THE CALLER. The life cycle of the call invitation ends in failure.
RETURNED TO THE CALLER. The initial state of a call invitation (idle).
RETURNED TO THE CALLER. The call invitation is received by the callee.
RETURNED TO THE CALLER. The call invitation is declined by the callee.
FOR INTERNAL USE ONLY. The call invitation is sent to the callee.
RETURNED TO THE CALLER. The call invitation is accepted by the callee.