Why 5G Core(5GC) is Different than EPC?

3GPP has found itself in a potentially complicated scenario, with two network topologies on the table. 

As a result, core network solutions may change based on how communication service providers install their radio networks, which technology they use for coverage bands, and which technology they use for capacity bands.

The primary distinction between 5G Core (5GC) and EPC is that 5GC’s control plane (CP) functions interact in a Service-Based Architecture (SBA). 

Access and Mobility Functions (AMF) and Session Management Functions (SMF) have a distinct functional separation in 5GC’s CP’s structure, which is another key difference from EPC.

The Network Repository Function (NRF), a crucial Network Function (NF) of SBA, offers NF service registration and discovery, allowing NFs to locate relevant services in one another. 

SBA principles apply solely to interfaces between CP functions inside 5GC, excluding interfaces to Radio Access Network (RAN), user equipment, or user plane (UP) functions (N1, N2, N3, N4, N6, and N9).

5GC contains the separation of UP and CP operations of the gateway, which is an advancement of EPC Release 14’s gateway CP/UP separation (CUPS).

A separate Authentication Server (AUSF) and numerous new functions, such as the Network Slice Selection Function (NSSF) and the Network Exposure Function (NEF), are also among the changes (NEF).