Fronthaul

Fronthaul is the network segment between the Remote Radio Head (or O-RAN Radio Unit) and the centralised baseband processing in Cloud RAN and vRAN architectures. It typically uses CPRI or the packet-based eCPRI over fibre, with strict latency and synchronisation requirements. Some functional splits expose unciphered user data, so fronthaul must be physically protected or encrypted with MACsec or IPsec.

Categories: Radio Access NetworkSecurity ControlsCloud and Virtualization

Fronthaul 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.

Security controls span signaling firewalls (SS7/Diameter/GTP screening), transport encryption (IPsec, TLS, PRINS), identity and access on OSS/BSS, and monitoring at both packet and log level. Controls are audited against GSMA FS.11/FS.19/FS.20/FS.36.

To place Fronthaul in the wider telecom-security picture, review IGW, RRH, 1G, 2G, 6G and A5/0 — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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