A method for operating a User Equipment (UE) is disclosed, the UE configured to connect to a communication network. The method comprises: indicating to the communication network an Integrity Protection for User Plane (IPUP) mode supported by the UE when requesting registration with the communication network. The IPUP mode comprises one of: use of Integrity Protection for User Plane data exchanged with the UE, non-use of Integrity Protection for User Plane data exchanged with the UE, or use of Integrity Protection for User Plane data, and non-use of Confidentiality Protection for User Plane data.