Case 1 : The UE try to attach with IMSI. And there is no the UE Context in Network (MME).Case 2 : The UE try to attach with GUTI and MME is unchanged. And there is no the UE Context in Network (MME).Case 3 : The UE try to attach with GUTI and MME is changed. And there is no the UE Context in Network (MME).Case 4 : The UE try to attach with GUTI and MME is unchanged. And there is the UE Context i..