Certification Authority (CA)

A Certification Authority is the trusted third party that issues and revokes X.509 certificates, binding a public key to a verified subject identity. Public CAs (subject to CA/Browser Forum rules and Certificate Transparency) issue certificates for the public web; private CAs serve enterprise PKIs and operator infrastructure such as 5G inter-NF mTLS, SEPP authentication, and IPsec tunnels. CA security, root key protection, issuance audit, and revocation hygiene, is the foundation of every PKI-based system.

Categories: Radio Access NetworkSignalingRoaming and Interconnect

Certification Authority (CA) in context

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

Signaling protocols carry the control-plane messages that set up calls, register subscribers and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA as top-tier telecom risk.

To place Certification Authority (CA) in the wider telecom-security picture, review mTLS, GRX, PLMN, PSTN, SUCI and Telecom Attack Surface Mapping: each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

Related topic hubs

  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.
  • SEPP Security N32-c/N32-f, PRINS, JWE and OAuth 2.0 at the 5G roaming edge.
  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
  • 5G Penetration Testing Pentesting the 5G core, SBA, SEPP, and gNB interfaces.

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.