The ‟User Location Info” IE is included in ‟Create Session Request and is described in 3GPP TS 29.274 version 8.1.1 Release 8. The encoding for individual location identifiers (CGI, SAI, RAI, TAI, and ECGI) is also defined in the same reference (as shown in Figure: User location information).
The AP’s MAC@ and IP@ are provided to AAA server in RADIUS messages during EAP authentication and accounting. If AAA provides the cellular location (corresponding to this AP) in 3GPP attribute 3GPP-User-Location-Info in access-accept, and location reporting is enabled via CLI. The ULI IE is included in GTPv2 ‟create session request”. The 3GPP-User-Location-Info attribute is described in 3GPP TS 29.061 v9.3.0.