MNC (Mobile Network Code)

The Mobile Network Code is a two- or three-digit identifier (per ITU-T E.212) that, together with the Mobile Country Code (MCC), uniquely identifies a mobile operator within a country. The MCC+MNC pair forms the PLMN-ID broadcast on every cell and embedded in the IMSI/SUPI, and is used for network selection and roaming partner identification.

Categories: Radio Access NetworkRoaming and InterconnectIdentity and Subscriber

MNC 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.

Roaming and interconnect are where two operators, often with an IPX or GRX carrier in between, exchange signaling and user-plane traffic. Trust boundaries here are the primary attack surface for location tracking, SMS interception and fraud, which is why GSMA now mandates SEPP with PRINS on 5G interconnect.

To place MNC in the wider telecom-security picture, review iSIM, PLMN ID, SUPI, MCC, MNO and AKA.

Related terms

Related topic hubs

  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.
  • 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.
  • VoLTE Security IMS/VoLTE signaling risk: SIP, IMS-AKA, media plane attacks.

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.