Although there are few open-source core network projects, none of them are conformed to 3GPP Release 15 (R15). The free5GC is the first one in the world based on 3GPP R15. The ultimate goal of free5GC is to implement a full commercial, operational core network including Operation, AdministrationManagement (OAM), orchestrator,network slicing complied with 3GPP R15beyond.