Question: In an IP Multimedia Subsystem (IMS) architecture, what is the primary purpose of utilizing a DNS-based mechanism for selecting an Interrogating-CSCF (I-CSCF) when multiple I-CSCFs are deployed per operator?
Option 1: To prioritize traffic based on Quality of Service (QoS) requirements
Option 2: To enhance security by encrypting signaling messages between nodes
Option 3: To reduce the number of required I-CSCFs for each operator to a single node
Option 4: To dynamically forward requests to an appropriate I-CSCF based on factors like location or identity of the forwarding node
Explanation: The correct answer, Option 4, highlights the key benefit of using a DNS-based selection mechanism in an IMS architecture with multiple I-CSCFs per operator. This approach enables flexible and dynamic routing of requests to the most suitable I-CSCF based on criteria such as geographical location or the identity of the forwarding node, thereby improving efficiency and scalability in telecom networks.