Amazon S3 accelerates integrity checking of requests by up to 92%. For the first time in the cloud, you can choose from four supported checksum algorithms for data integrity checking on your upload and download requests. In addition, enhancements to the AWS SDK and S3 API significantly improve checksum efficiency, increasing the performance and reducing the cost of data validation. You can automatically calculate and verify checksums as you store or retrieve data from S3, and can access the checksum information at any time using a new S3 API or an S3 Inventory report. Using checksums for data validation is a best practice for data durability, and these capabilities increase the performance and reduce the cost to do so.
Source:: Amazon AWS