Signatures

Signature characteristics:

• must be creatable only by the signer
• must include information used to verify document integrity
• must be verifyable as legitimate signature

How it works:

• collect information about the document (CRC)
• add to information about signer
• encrypt this information using signer's private key

Now...

• anyone can verify signature by decrypting using signer's public key
• document integrity can be verified by comparing CRC with value included in signature
• document content may or may not be encrypted

We still need a mechanism for verifying public keys - Certificates

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PKI - Introduction and Overview First presented at ACM SIGUCCS CSMS99, March 8, 1999 Last revised October, 1999 Questions to david_henry@umail.umd.edu