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Besides protecting communications certificates also can protect content and verify the identity of the

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content.

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Author.

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When you receive a message with confidential content, you need to be confident about two things that

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the message was not modified in transit and the identity of the author is verifiable.

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You can also use certificates to protect and verify content and to verify the identity of an author.

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It is common for a user to sign a document digitally.

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No digital signatures when a person digitally signs a document in an application such as an email or

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a microsoft Word document.

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Sure, she confirms that the document is authentic.

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In this context, authentic means that it is known who created and signed a document and that no one

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has altered the document since a public key infrastructure or PGI cannot achieve this level of security

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compared to the web server from the previous topic.

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A user also can have a certificate for the public and private key pair.

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This certificate is used in the process of digital signing when an author digitally signs a document

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or a message.

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The operating system on his or her computer creates a message.

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Cryptographic digit digest that ranges from 128 bit to 256 bit number.

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It is generated by running the entire message through a hash algorithm.

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This number then is encrypted by using the author's private key and it is added to the amount of the

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document or message.

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When the document or message reaches the recipient.

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It will go through the same hash algorithm as when the author digitally signed it.

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Also, the recipient uses the author's public key to decrypt the digest that is added to the message

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after it is decrypted.

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It is compared to the digest the recipient has generated and if they are the same, the document or

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the message was not altered urine.

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Transport also if the recipient can decrypt their budget by using the authorities public key.

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This meant the digest was encrypted by using the author as private key, and that confirms the author's

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identity as the end.

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The recipient also verifies the certificate that proved the authors identity.

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During this check, the recipient also verifies the validity period serial subject name and certificate

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chain trust.

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Nelson wrote about implementing, implement and digital signatures.

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To implement digital signatures.

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An internal communications unit to issue certificates based on the user template.

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You also issue certificates to all users.

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Who use digital signatures.

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Who can issue the certificate without any user intervention?

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If you use auto enrolment also users must use an application that supports content signing.

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For example, you can use digital ID digital signatures by default in Windows.

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Microsoft Word and Microsoft Outlook.

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Digital signatures are ready to use after the application issues and configure the certificate after

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you sent digitally signed content outside of your organisation.

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You might experience you trust issues in this scenario.

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A recipient is not in the same EDS domain as the author, so it does not trust the CAA that issued the

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certificate for the digital signature.

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Although this type of digital signature will still be valid from a content production perspective,

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an application will probably generate a warning on the recipient side.

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If you need to send digitally signed content to recipients outside of your organisation, it is recommended

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that you buy a certificate from a public global trusted see.

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Next up, we'll have a demonstration where we'll see how to sign a document digitally.