Insert Subscriber Data is a Subscriber Data Handling procedure in GSM services. This procedure is used to manage the subscription data of subscriber in MME and SGSN over S6a/S6d interface. IDR is invoked by Home Subscriber Server for subscription data handling. IDR is MAP subscriber management service utilized in GSM/UMTS networks, standardized by 3GPP, and defined in the MAP specification, TS 29.002. This service is used to provide specific subscriber data in the following environments: by an HLR to update a VLR, by an HLR to update a SGSN, and by an HSS to update a MME via IWF in an EPS. This service is primarily used by the home subscriber management entity to update the serving subscriber management entity when there is either a change in a subscriber parameter, or upon a location updating of the subscriber.