MDF2 (Mediation and Delivery Function 2 (IRI))

Also known as: Mediation Delivery Function 2

MDF2 is the 3GPP lawful-interception function (TS 33.126, TS 33.127, TS 33.128) that mediates Intercept Related Information from POIs, applies correlation and formatting, and delivers it to the LEA over the LI_HI2 interface. It is the IRI counterpart of MDF3 and is deployed inside the operator's segregated LI domain.

Categories: Threats and AttacksProtocols and StandardsOperations and Business

MDF2 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 MDF2 in the wider telecom-security picture, review Patch, 3GPP, Attack Surface Mapping, BGP, Charging System and Cipher Downgrade Attack — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.