Question: What is a key consideration for the implementation of Cost Control mechanisms in Release 99, regarding compatibility with future network upgrades?
Option 1: Ensuring backward compatibility to allow Release 99 terminals to function with future Advice of Charge implementations in the Home Environment.
Option 2: Mandating the immediate adoption of full Cost Control requirements, superseding Advice of Charge.
Option 3: Implementing a hybrid model that phases out Advice of Charge for new terminals while maintaining it for existing ones.
Option 4: Focusing solely on reducing signaling overhead related to charging without considering terminal compatibility.
Explanation: This option is correct because, as per the provided context, the Release 99 standards are designed to be forward-thinking, allowing for the introduction of new Cost Control features in a backward-compatible manner. This ensures that terminals conforming to Release 99 standards can continue to support Release 99 service requirements even when operating with future implementations of Advice of Charge in the Home Environment, thus maintaining seamless functionality across network upgrades.