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When a federated file is first accessed, a SHA-1 hash is computed and cached. This may take a while for large files. Just like As is the case for any Fedora node, a request may be made through a web browser or client to recompute and compare the checksum of a file.
In the HTML view, beside the "digest" property for the content, there's a "check fixity" link which will recompute the checksum and compare it with the last oneolder SHA-1. This feature is documented.
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