The present document specifies the technical realization of the 5GC Service Based Architecture@ protocols supported over the Service Based Interfaces@ and the functionalities supported in the Service Based Architecture. The service requirements for the 5G system are defined in 3GPP TS 22.261 [2]. The system architecture requirements are defined in 3GPP TS 23.501 [3] and the procedures and flows in 3GPP TS 23.502 [4]. The design principles and documentation guidelines for 5GC SBI APIs are specified in 3GPP TS 29.501 [5].