Question: What is an appropriate use case for the private message mechanism in E-UTRAN's S1 Application Protocol (S1AP)?
Option 1: Implementing standardized, basic functionalities required for multivendor interoperability.
Option 2: Deploying a new, widely adopted feature across all vendors without prior standardization.
Option 3: Enhancing security protocols for sensitive user data transmission.
Option 4: Evaluating new, non-standardized algorithms/features by vendors before potential standardization.
Explanation: The private message mechanism is intended for non-standard use, such as allowing vendors to test and evaluate new features or algorithms that are not yet part of the standardized basic functionality. This aligns with innovating and testing before seeking standardization, ensuring multivendor interoperability for core functions while fostering innovation at the edges.