5G

5G is the fifth generation of mobile network technology, specified by 3GPP, whose security architecture is set out in 3GPP TS 33.501. Like 4G, it authenticates the subscriber’s SIM to the network and the network to the SIM. Where encryption is enabled, it protects the radio link between the handset and the base station, not the traffic end to end. The change commonly taught is identity protection: 5G is described as concealing the subscriber’s permanent identifier before it is sent over the air, where the operator enables this, so a fake base station such as an IMSI catcher cannot simply ask for it.

5G also introduces network slicing, which runs logically separate networks on shared operator infrastructure. Slicing is a segmentation mechanism, and how well one slice is isolated from another depends on how the operator implements it. It counts as a control only where that isolation is specified and assured. Forcing a handset to downgrade to an older generation remains a commonly taught threat.

Exam relevance: a scenario is likely to test whether a candidate treats 5G as a reason to drop other protection. Sensitive traffic still needs TLS or a VPN. Candidates are also expected to avoid two common errors: that 5G introduced mutual authentication (4G already had it), and that slicing is a security feature by definition.