eNodeB (Evolved Node B)

Also known as: eNB, Evolved NodeB

The eNodeB is the 4G LTE base station, the radio node that terminates the LTE air interface to the UE. It handles scheduling, radio resource management and handovers, and connects to the Evolved Packet Core over S1-MME (to the MME) and S1-U (to the Serving Gateway). It is the LTE evolution of the 3G Node B and the predecessor of the 5G gNodeB, and its backhaul, management interfaces and X2 links are part of the RAN attack surface.

Categories: Radio Access NetworkCore NetworkSecurity Controls

eNodeB 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 eNodeB in the wider telecom-security picture, review gNodeB, Base Station (BS), MME, S1AP, LTE and NRF Poisoning.

Related terms

Equipment

Base stations (BTS, NodeB, eNodeB, gNodeB)

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