Editing My 4G lawful interception notes (section)

== EPS Multimedia ==

This includes IMS-based voice (VoLTE) or other services.

33.108 12.1.4
Lawful intercept identifier (LIID) and Network identifier are same as data. The correlation number is unique per VoIP session.

For IMS-based VoIP, the S-CSCF and optionally, the P-CSCF provide the IRI events. For IMS-based VoIP, the functional element that provides the communication content (CC) interception depends on the call scenario and network configuration.

The term "CC Intercept Function" is a generic term used to denote a network function that has access to the voice media of an intercepted call. The term "CC Interception Triggering Function" is a generic term used to denote a network function that provides a trigger to intercept the CC.

As described in 33.107, CC interception may be done by one of the following functional elements (referred to as CC Intercept Function)
* PDN-GW/GGSN
* IMS-AGW
* TrGW
* IM-MGW
* MRF

The trigger to perform the CC interception at the above functional elements may be provided by the following functional elements (referred to as CC Interception Triggering Function)

{| class="wikitable sortable"
|-
! CC Interception Triggering Function !! CC Intercept Function
|-
| P-CSCF|| PDN-GW/GGSN
|-
| P-CSCF || IMS-AGW
|-
| IBCF || TrGW
|-
| MGCF || IM-MGW
|-
| S-CSCF || MRF
|}