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Object Storage Service:How to verify the integrity of data uploaded to OSS from clients

Last Updated:Jan 22, 2025

Alibaba Cloud Object Storage Service (OSS) provides the MD5 and CRC-64 data verification mechanisms to ensure the consistency and integrity of uploaded and downloaded data. You can use the preceding verification mechanisms in your projects to ensure the reliability of data transmission and storage and the stability of the business system.

Verification mechanisms

  • MD5: When you upload an object, you can include the MD5 value of the object. After OSS receives the object, the system automatically compares the received MD5 value with the MD5 value calculated based on the actual object content to ensure data consistency.

  • CRC64: OSS can return a CRC-64 value of an object uploaded by using any of the methods provided. The client compares the CRC-64 value with the CRC-64 value calculated on the local machine to verify data integrity.

Suggestions

For information about how to ensure that an uploaded object in OSS is consistent with the local file, see Can I use ETag values as OSS MD5 hashes to check data consistency? For information about how to verify data integrity during data upload and download, see Check data integrity by using CRC-64.