There are two roaming approaches: Local Breakout and Home Routed
- In LocalBreakout, data traffic is routed directly from the visiting network (VPLMN) to the DN while authentication and handling of subscription data is handled in the Home network (HPLMN). Basic roaming Policy and Charging is applied by the Visiting PCF and CHF as per roaming agreements. In this case only signaling data is routed to Home network.
- In HomeRouted, the visiting network data traffic is routed to DN via Home network. It provides more control to the Operators to offer roaming services, policy and charging the subscribers. However, it adds extra layer of complexity and lag in the network. Along with the signaling data, bearer data is also routed to the Home network.
LinkedIn:
SEPP (Security Edge Protection Proxy) acts as a service relay between VPLMN and HPLMN for providing secured connection as well as hiding the network topology.