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Public key infrastructure

(also PKI)

Public key infrastructure definition

Public key infrastructure is a structure that safeguards communications and confirms the identities of users and devices within a network. Using cryptographic methods, protocols, and a digital certificate system, PKI ensures data remains confidential and authentic, and maintains its integrity. This infrastructure is essential for secure online interactions, such as encrypted emails, virtual private networks (VPNs), and protected web browsing experiences.

See also: certificate authority server, security certificate, SSL encryption

Public key infrastructure components

  • Certification Authority (CA): A trusted entity that issues and manages digital certificates, ensuring their validity and authenticity.
  • Registration Authority (RA): A delegate of the CA responsible for verifying user identities before requesting digital certificates from the CA.
  • Digital certificate: An electronic document containing a user or device's public key, issued and signed by a CA to confirm the owner's identity.
  • Certificate Revocation List (CRL): A list of revoked digital certificates, which are no longer valid due to expiration or compromise.

Public key infrastructure advantages

  • Provides end-to-end encryption and ensures data confidentiality.
  • Validates user and device identities through digital certificates, enhancing security and trust.
  • Enables secure communications between unknown parties over untrusted networks.

Public key infrastructure drawbacks

  • Dependency on trusted CAs, which can become targets for cyberattacks or compromise.
  • The complexity of managing and maintaining PKI infrastructure may be challenging for some organizations.

Tips for using public key infrastructure

  • Use a reputable and trustworthy CA for digital certificates.
  • Regularly update your Certificate Revocation List (CRL) and monitor for revoked certificates.
  • Implement robust PKI policies and procedures to ensure system integrity.