Question: During Rx interface initialization between an Application Function (AF) and a Policy and Charging Rules Function (PCRF), what specific identifiers are advertised in the Capabilities-Exchange-Request and Capabilities-Exchange-Answer commands to indicate support for the Rx application?
Option 1: Only the Auth-Application-Id AVP with a generic Diameter value
Option 2: Both the Auth-Application-Id AVP with the Rx specific Application identifier and the Vendor-Id AVP with the 3GPP (10415) value
Option 3: Just the Vendor-Id AVP with the 3GPP (10415) value, without any application-specific identifier
Option 4: Neither Auth-Application-Id nor Vendor-Id AVPs are used for this purpose in Rx interface initialization
Explanation: To ensure interoperability and specify the use of the Rx interface, both the application's unique identifier (carried by the Auth-Application-Id AVP) and the vendor's identifier (3GPP, carried by the Vendor-Id AVP) must be communicated. This dual approach confirms that the connection is established for policy and charging control over the Rx reference point.