Are messages sent to DataSet stored encrypted?

We have our own encryption algorithm for data encryption. Therefore, we actually encrypt the data before it is saved to the S3 bucket as a flat-file. When you run a search query, we first retrieve the data based on the query time range, then decrypt the files before the results eventually return to the web application. 

There is no database used for storing the data, so all of your data is encrypted at rest in S3 buckets.