Digital Certificate

• A digital certificate is used to verify that a user sending a message is who they claim to be, and to provide the receiver with the means to encode a reply.

• Those wishing to send encrypted messages obtain a digital certificate from a certifying authority.
  • The certifying authority issues an encrypted digital certificate.

• The recipient of an encrypted message uses the certifying authority's public key to decode the digital certificate attached to the message.
  • The recipient verifies it as issued by the certifying authority.
  • Then it obtains the sender's public key and identification information held within the digital certificate.
  • With this information, the recipient can then send an encrypted reply.

• The most widely used standard for digital certificates is X.509.
  • Digital certificates are sometimes called X.509 certificates.

What are the contents of digital certifcates?

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© 2006 John Michael Pierobon

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