What feature allows for maintaining the integrity of the indexed data in Splunk Enterprise Security?

Indexer acknowledgement is essential for maintaining the integrity of indexed data in Splunk Enterprise Security. This feature ensures that data sent to the indexer is properly received and acknowledged by the indexer before it can mark the data as successfully indexed. When a forwarder sends data to an indexer, it awaits a confirmation that the data has been received without errors. This process helps to prevent data loss and ensures that all events are accounted for correctly, thus maintaining the integrity of the data within Splunk.

Other features, while important for data management and confidentiality, do not directly address the integrity of data during the indexing process. Data retention policies manage how long data is stored before being deleted, access control lists determine who has permissions to access or manipulate the data, and data encryption protects the contents of the data during transit or storage. However, none of these features provide the same level of assurance that the data is accurately captured and acknowledged during the indexing process as indexer acknowledgement does.