Lawful Interception Architecture

The lawful-interception architecture standardised by ETSI and 3GPP comprises three handover interfaces: HI1 for warrant administration, HI2 for intercept-related information (call records, location, signalling metadata), and HI3 for content of communication. Inside the operator network, Intercept Access Points capture traffic and forward to a Mediation Function that delivers via HI2/HI3 to the law-enforcement monitoring facility.

Categories: Radio Access NetworkSignalingThreats and Attacks

Lawful Interception Architecture 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.

Signaling protocols carry the control-plane instructions that set up calls, register subscribers, hand over sessions 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 FS.11 / FS.19 / FS.20 as a top-tier telecom risk.

To place Lawful Interception Architecture in the wider telecom-security picture, review Lawful Intercept, Lawful Interception, IAP, Revenue Assurance, Lawful Interception Abuse Risk and Roaming Security Architecture.

Related terms

Equipment

Lawful interception systems (ADMF, mediation, HI1/2/3)

Articles in the P1 mobile network security guide

Related topic hubs

  • SS7 Security SS7/MAP/CAP/SCCP attacks and defenses across 2G/3G interconnect.
  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
  • Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.

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.