Lawful Interception

Also known as: LI, Lawful Interception

Lawful Intercept (LI) is the legally authorised capability that allows law enforcement agencies to obtain communications content and related metadata from telecom operators under judicial or administrative warrant. Standards such as ETSI TS 102 232 and 3GPP TS 33.126/33.127/33.128 define the handover interfaces, data formats and 5G-specific architecture (LIPF, LICF, MDF2/MDF3) so operators can deliver intercepted traffic securely to authorised agencies.

Categories: Radio Access NetworkSignalingThreats and Attacks

Lawful Intercept 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 Intercept in the wider telecom-security picture, review Lawful Interception Architecture, Lawful Interception, Lawful Interception Abuse Risk, Telecom Penetration Testing, CALEA and GSM.

Related terms

Equipment