Public Key Infrastructure

Definition

Public Key Infrastructure (PKI) is a framework that uses a combination of hardware, software, policies, and procedures to manage digital certificates and public-key encryption. PKI enables secure communication and authentication over the internet by allowing users to exchange information securely through the use of cryptographic keys. It plays a crucial role in establishing trust among parties in online transactions and communications.

5 Must Know Facts For Your Next Test

1. PKI relies on asymmetric encryption, which uses a pair of keys: a public key for encryption and a private key for decryption.
2. The trust model in PKI is hierarchical, where root CAs issue certificates to intermediate CAs, which can then issue certificates to end entities.
3. PKI supports various security protocols, such as SSL/TLS, ensuring secure communication for online activities like banking and shopping.
4. Revocation mechanisms, such as Certificate Revocation Lists (CRLs) and Online Certificate Status Protocol (OCSP), help manage invalid or compromised certificates.
5. PKI is essential for implementing secure email (S/MIME) and document signing, enhancing confidentiality and authenticity in communications.

Review Questions

• How does Public Key Infrastructure facilitate secure online communication between users?
  • Public Key Infrastructure facilitates secure online communication by using asymmetric encryption, where each user has a public key for encryption and a private key for decryption. When one user wants to send secure information to another, they encrypt the message with the recipient's public key. Only the recipient can decrypt it with their private key, ensuring that only authorized parties can read the transmitted data.
• What role does a Certificate Authority play in maintaining the integrity of Public Key Infrastructure?
  • A Certificate Authority (CA) plays a vital role in maintaining the integrity of Public Key Infrastructure by issuing digital certificates that verify the identities of individuals or organizations. The CA ensures that the information contained in the certificate is accurate and trustworthy. When users receive a certificate signed by a CA, they can trust that the entity behind the certificate is legitimate, which is essential for secure communications and transactions.
• Evaluate the impact of certificate revocation mechanisms on Public Key Infrastructure's effectiveness in secure communications.
  • Certificate revocation mechanisms significantly impact Public Key Infrastructure's effectiveness by ensuring that compromised or invalid certificates do not undermine security. Mechanisms like Certificate Revocation Lists (CRLs) and Online Certificate Status Protocol (OCSP) allow users to check whether a certificate is still valid before relying on it for secure communications. By promptly revoking compromised certificates and informing users about their status, these mechanisms help maintain trust in PKI systems and reduce the risk of data breaches or unauthorized access.

Related terms

Digital Certificates: Digital certificates are electronic credentials used to verify the identity of individuals or organizations in a digital environment, ensuring that data transmitted is secure.

Certificate Authority (CA): A Certificate Authority is a trusted entity that issues digital certificates, verifying the identity of the certificate requestor and ensuring the integrity of the communication.

Encryption: Encryption is the process of converting plaintext information into ciphertext to prevent unauthorized access, ensuring that only authorized parties can read the data.