Kein Folientitel

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Public Key Infrastructure for Digital Signatures
Christian Ploninger Technische Universitaet Wien
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Contents

• Asymmetric Encryption
• Key-Person-Binding Problem
• Public Key Infrastructure
• - Components
• - Functionality

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Asymmetric Encryption

• Authenticity
• Secrecy
• Integrity

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Asymmetric Encryption
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Key-Person-Binding

• Certificates
• Trusted Third Parties

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PKI - Components

• Local Registration Authority (LRA)
• Certification Authority (CA)
• Root Certification Authority (RCA)

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PKI - Requesting a Certificate

• Verify User Identity

• Verify Message Authenticity

• Create User Key-pair

• Issue Certificate

• Sign Certificate

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PKI - Functionality

• Key Creation for CA
• User Registration
• Key Creation for Users
• Issue Certificates

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PKI - Functionality

• Directory Service
• Revoke Certificates
• Timestamp Service
• Personalize Private Keys

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Conclusion

• Asymmetric Encryption is not enough
• Key-Person-Binding Problem
• PKI solves this problem

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Recommended Readings

• Security in Open Networks,
• Dusemund, Becker, Gollan, Engel and Meinel,
• http//www.ti.fhg.de/publikationen/technische_beri
  chte/2000/prep1500.de.ps
• Ten Risks of PKI,
• Carl Ellison and Bruce Schneier,
• http//www.counterpane.com/pki-risks.pdf
• Digitale Signatur,
• Frank Bitzer and Klaus Brisch,
• Springer Verlag, ISBN 3-540-65563-8