Question: In the context of Diameter-based protocols for Short Message Service (SMS) in IMS, what information does the Originating-SIP-URI Attribute Value Pair (AVP) typically contain regarding the sender's identity?
Option 1: The sender's MSISDN along with their IMS Public Identity
Option 2: Only the sender's IMS Public Identity without any MSISDN reference
Option 3: A temporary identifier generated for SMS delivery, not linked to the sender's IMS Public Identity or MSISDN
Option 4: The sender's IP address used for initiating the SMS session
Explanation: In the context of MSISDN-less SMS delivery in IMS, the Originating-SIP-URI AVP contains the Public identity of the IMS User Equipment (UE) without including the Mobile Subscriber Integrated Services Digital Network Number (MSISDN), supporting scenarios where the traditional MSISDN is not utilized for message routing and delivery.