The MinIO server runs a key-derivation algorithm to generate the KEK using a pseudo-random function ([PRF](#prf)):
`KEK := PRF(EK, IV, context_values)` where:

- [EK](#ek): is the external key. In case of SSE-C this is the client-provided key. In case of SSE-S3  this is secret key generated by the KMS. For further details see [SSE-C](#Server-Side-Encryption-with-client-provided-Keys) or [SSE-S3](#Server-Side-Encryption-with-a-KMS).

Status of delete marker replication can be viewed by doing a GET/HEAD on the object version - it will return a `X-Minio-Replication-DeleteMarker-Status` header and http response code of `405`. In the case of permanent deletes, if the delete replication is pending or failed to propagate to the target cluster, GET/HEAD will return additional `X-Minio-Replication-Delete-Status` header and a http response code of `405`.

NOTE:

- `timeToFirstByte` and `timeToResponse` will be expressed in Nanoseconds.
- Additionally in the case of the erasure coded setup `tags.objectErasureMap` provides per object details about
  - Pool number the object operation was performed on.
  - Set number the object operation was performed on.