LTE; 5G; Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); Lawful Interception (LI) architecture and functions (V15.1.0; 3GPP TS 33.127 version 15.1.0 Release 15)
The present document specifies both the architectural and functional system requirements for Lawful Interception (LI) in 3GPP networks. The present document provides an LI architecture supporting both network layer based and service layer based Interception. National regulations determine the specific set of LI functional capabilities that are applicable to a specific 3GPP operator deployment.