Technical information about ‘Safe Stamper File’ Certification of digital files

JANUARY, 2017

1.- How it works: Users must access the service from Safe Stamper’s official site. From there, they enter the “Files” service and upload the file they wish to certify. The file is uploaded to Safe Stamper’s servers, which work as witnesses of the existence of the file at that exact date and hour. The duration of the process to submit and certify the file will depend on the size of it. After it has finished, the user can download a PDF certificate that includes the digital hashes to identify the file. The certificate includes a URL that enables other people to check it as long as the user hasn’t chosen to restrict the access with a password.

2.- Tecnología del documento de certificación The PDF certificate includes 4 hashes or cryptographic algorithms, namely MD5, SHA1, SHA256 and SHA512. Once they are obtained, they appear on the PDF, along with the date when the file was submitted, the name and size of the file. The document is digitally signed and timestamped. These hashes are calculated based on the file submitted by the user. They are the ones to allow, if necessary, to demonstrate with certainty which is the file whose existence was certified. This is because only that particular file will be able to generate the exact same hashes. The certificate constitutes reasonable and valid evidence to prove the existence of the file, at the specified date, thanks to the recognized electronic signature of the organization behind Safe Stamper: Safe Creative SL.

www.safestamper.com

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www.safestamper.com

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