HI3 (Lawful Interception (Handover Interface 3))

The interface for intercept-related information from the network to law enforcement per ETSI LI model. HI3 provides metadata about communications without intercepting content.

Categories: Threats and AttacksProtocols and Standards

HI3 in context

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking. The common thread is that most attacks exploit the inherited trust model of legacy signaling protocols.

Telecom security is written into standards from 3GPP, GSMA, ETSI, IETF and ITU-T. Understanding which body owns which specification, and how they interlock, is essential for both design and audit work.

To place HI3 in the wider telecom-security picture, review HI2, HI1, ETSI TS 103 221, X2 (LI), IRI and HLS: each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

Related topic hubs

  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.

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.