HI1 (Lawful Interception (Handover Interface 1))

HI1 in context

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking and lawful-interception abuse. The common thread is that most attacks exploit the inherited trust model of legacy signaling. SS7 and Diameter were designed for a closed operator community that no longer exists.

Telecom security is written into standards from 3GPP, GSMA, ETSI, IETF and ITU-T. Understanding which body owns which specification, and how the specs interlock (for example 3GPP TS 33.501 with GSMA FS.34 for 5G SBA security), is essential for both design and audit work.

To place HI1 in the wider telecom-security picture, review HI2, HI3, X1, X2 (LI), ETSI TS 103 221 and Mediation Device (Lawful Interception).

Related terms

• HI2
• HI3
• X1
• X2 (LI)
• ETSI TS 103 221
• Mediation Device (Lawful Interception)
• N4
• IRI

Equipment

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

• ETSI TS 103 221
• HI2
• HI3
• Lawful Intercept
• Lawful Interception
• Lawful Interception Abuse Risk
• Lawful Interception Architecture
• Mediation Device (Lawful Interception)
• X1
• X2 (LI)
• All 11 terms

Articles in the P1 mobile network security guide

Related topic hubs

• Diameter Security 4G/LTE Diameter threats across IPX/roaming and DEA defenses.
• Diameter Firewall GSMA FS.19 screening at the Diameter Edge Agent on S6a/S9/S13.
• 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.