Diagram showing the communications protoicols (SOAP, REST, or Other) supported by each API.  BRM WSM and PDC Web Service use the SOAP protocol.  BC REST, BRM RSM (TMF), PDC RSM (TMF), PDC REST, ECE REST (TMF), and HTTP2 (with Nchf and Nnrf) all use the REST protocol.  JCA, PCM API (with Java, C++, and Perl), Diameter (with Gy, Sp, and Sy), and RADIUS all use another protocol.
Perl C++ Java Sy Sp Gy Nnrf Nchf RADIUS Diameter HTTP2 ECE REST (TMF) PDC REST PDC RSM (TMF) PDC Web Service JCA BRM RSM (TMF) BC REST WSM