Question: In a 3GPP network, when multiple Certification Authority (CA/RA) servers are deployed for different vendors within an operator's network, how is the Fully Qualified Domain Name (FQDN) of a specific CA/RA server constructed to include vendor identification?
Option 1: cara.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org/<VendorID>
Option 2: vendor<ViD>.cara.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Option 3: <VendorID>_cara.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Option 4: cara_<VendorID>.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Explanation: In scenarios where multiple CA/RA servers are used, one for each vendor, the FQDN construction requires the inclusion of a <vendor ID> label. According to specifications for such deployments, this label is added in front of the 'cara' label, resulting in the format vendor<ViD>.cara.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org. This ensures unique identification of each CA/RA server based on both the operator's network identifiers (MNC and MCC) and the vendor's ID.