Final answer:
The most cost-effective solution for the digital media agency's requirements would be to use Amazon S3 Intelligent-Tiering, which automatically moves files to the appropriate access tier, ensuring immediate access while optimizing storage costs.
Step-by-step explanation:
In this case, the digital media agency is looking for a cost-effective solution to handle files that are frequently accessed for only the first 30 days after their creation but need to be retained for five years. Since immediate accessibility is required, utilizing Amazon S3 Intelligent-Tiering would be a suitable strategy. This service automatically moves the files to the most cost-effective access tier based on changing usage patterns without affecting performance or operational overhead.
For the first 30 days, the files can remain in the frequent access tier where retrieval is instantaneous, addressing the need for frequent access during this period. After the initial 30 days, S3 Intelligent-Tiering can transition these files to the infrequent access tier, which is cheaper and still provides immediate access, though the files are accessed less often. Since the agency's files contain critical business data and cannot be easily reproduced, this approach ensures data durability and availability while optimizing costs.
Additionally, it is essential to remember that the solution should comply with the agency's data retention policy, ensuring files are preserved for the mandated 5-year period before deletion.