Open RAN

Open RAN is an industry initiative led by the O-RAN Alliance to disaggregate the RAN into multi-vendor components, Radio Unit, Distributed Unit, Centralised Unit, and a RAN Intelligent Controller, connected by open, standardised interfaces such as the Open Fronthaul, E2, A1, and O1. The benefits are vendor diversity and innovation; the security implications are a much larger attack surface, complex inter-vendor integration, and new exposed interfaces that require dedicated threat modelling and the controls described in O-RAN WG11 specifications.

Categories: Radio Access NetworkCore NetworkThreats and Attacks

Open RAN in context

The radio access network is the layer where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations, downgrade attacks and jamming, and defenses hinge on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

The mobile core is where subscriber sessions, mobility and policy live. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF. Core exposure is the difference between a single-subscriber leak and a fleet-wide breach.

To place Open RAN in the wider telecom-security picture, review RAN, O-RAN Interfaces (A1, E2, O1, O2), Base Station (BS), BTS, Jamming and Threat Intelligence.

Related terms

Equipment

O-RAN units and RIC (O-RU, O-DU, O-CU, RIC, SMO)

Articles in the P1 mobile network security guide

Related topic hubs

  • Open RAN Security O-RAN xApp/rApp, E2/A1/O1 interfaces and RIC security.
  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
  • 5G NEF Security Network Exposure Function security in the 5G core.

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.