Access-Network-Info  AVP ( 1526 )

For a Trusted WLAN, this AVP contains the SSID of the WLAN and may contain at least one of the following elements: the BSSID, the civic address of the access point to which the UE is attached, the Logical Access ID associated to the access point to which the UE is attached. It may also contain the name of the TWAN operator. For an untrusted WLAN, it contains the same information as specified above for a trusted WLAN, where the operator name indicates the WLAN operator name. .

Reference: 3GPP TS 29.273-f30   View