Technical Committee (TC) Lawful Interception (LI) Activity Report 2021

Chair: Martin Kissel, Telefonica

Responsible for developing standards that support the technical requirements of national and international obligations for law enforcement (including lawful interception and lawful disclosure).

Lawful Interception (LI) and Lawful Disclosure (LD) play a crucial role in the growth and development of the Information Society, by helping law enforcement agencies (LEAs) to investigate terrorism and serious criminal activity.

Bringing together the interests of governments and law enforcement agencies as well as mobile network operators and equipment vendors, ETSI’s committee on Lawful Interception (TC LI) develops standards supporting common international requirements for LEAs, including the interception of content and disclosure of electronic communications related data with supporting standards for warrantry and internal interfaces.

Working in partnership with other ETSI technical bodies, projects and partnerships, TC LI develops standards to support industry compliance with the requirements of national and international law. The committee’s role in these partnerships is in the development and publication of control and handover interfaces, and of rules for the delivery of technology specific interception or retained data.

TC LI maintains close liaison with a large number of bodies to make sure that LI and LD requirements are taken into account in their work. Regular interactions occur either through official liaisons statements or through informal reports at TC LI meetings by liaison officers who are delegates who also participate in the group(s) they report from. These bodies notable include:

  • 3GPP SA (Service and System Aspects), especially SA3-LI (Lawful Interception), as well as SA3 (Security), SA2 (Architecture), SA5 (Telecom Management) and SA1 (Services);
  • 3GPP CT (Core Networks and Terminals) Plenary;
  • ETSI related groups: oneM2M/SmartM2M; TCs CYBER, ITS and TCCE; ISGs NFV, MEC, ENI, NIN;
  • GSMA;
  • ITU-T SGs 13 (Future networks & cloud) and 17 (Security).

During 2021 the committee continued to update its suite of various standards, specifications and reports relating to LI and LD.

Initially published in 2020 and subsequently updated this year, Technical Specification TS 103 707 represents a major collaborative project to define handover details for LI functionality in OTT (Over-The-Top) messaging services delivered over HTTP/XML. Development of this specification has featured inputs from a number of ETSI Members from the non-traditional telecoms world, including providers OTT (Over-The-Top) messaging services.

Published in November 2021, TR 103 727 presents a library and mapping for LI and LD. The Technical Report describes national parameters and implementations in the context of the Inter LEA Handover Interface (TS 103 462) and cross-border data exchange in criminal matters, for example through bilaterally agreed legal assistance, or using the secure European Judicial Network.

The committee made successive revisions to both parts of its specification [TS 103 221-1, TS 103 221-2] for internal network LI interfaces (X1 in part 1 and X2/X3 in part 2), covering connections between LI systems and (depending on the network) many network elements from different vendors. With a view toward the future, as network and services become virtualized, the X interfaces specifications intend to support newer implementations by ensuring that standard interfaces are available to the provisioning equipment or service, which should reduce complexity and cost for the Communication Service Providers.

We published successive revisions to our specification TS 103 120 of the Handover Interface 1 for warrant information.

We made further updates to our specification [TS 102 657] that details handover requirements and a handover specification for retained data.

We published several updates to our seven-part Technical Specification [TS 102 232-1, 102 232-2, 102 232-5, 102 232-7] that details Handover Interface and Service-Specific Details (SSD) for IP delivery. Ongoing work to update this multipart deliverable represents substantial effort by a group of top TC LI experts to ensure that ETSI continues publishing world-class LI and RD standards.

We revised our specification TS 101 331 on LI requirements of Law Enforcement Agencies to clarify multiple interception measures.

We updated our dictionary of parameters TS 103 280 that are commonly used in the context of multiple TC LI specifications.

In line with latest specification updates we revised our Technical Report [TR 102 503] that provides an overview of relevant Object IDentifiers (OID) used in LI and LD handling specifications by ETSI, and others produced by ITU-T and ISO.

See the full list of TC LI publications during 2021 here.

During the year the committee also made further progress on a number of newly-adopted and existing Work Items:

A new Technical Specification [TS 103 705] will specify flexible and extensible data structures for Lawful Disclosure for use in combination with existing ETSI handover interface standards.

Revisions are meanwhile in progress to Technical Specification TS 103 462 that specifies the LEMF to LEMF and/or the Coordination Function to LEMF interface to support (as a minimum) the European Investigation Orders (EIOs) and Production and Preservation Orders (EPOC) related to LI and/or LD.

During the year work progressed on three new Technical Reports:

TR 103 829 on IP address retention and traceability. This will serve as a guide for policymakers, communication service providers, and law enforcement agencies regarding the retention of IP addresses for law enforcement purposes.

TR 103 830 on LEA support services; Development and evaluation of technical capabilities. This will offer guidance to manufacturers, Communications Service Providers (CSPs), Law Enforcement Agencies (LEAs) and other stakeholders to provide support for development and evaluation of technical capabilities regarding LEA support services.

TR 103 854 on LEA support services; Interfaces for LD of vehicle-related data: scenarios, examples and recommendations. This report will describe interfaces that consist of requests (from a Law Enforcement Agency system) for vehicle-related data, and the responses (such as from an industry system) to those requests. This report will describe usage scenarios and makes recommendations for how the LEA/Industry interface could work.

Other deliverables in development include a TC LI strategy document. Its aim is to capture technology and legislative constraints, identifying where it is necessary to develop normative specifications based on technical requirements of networks and services as well as relevant legislation in EU and other regions.

See the full list of current TC LI Work Items here.