Public Key Infrastructure

Definition

Public Key Infrastructure (PKI) is a framework that uses public key cryptography to secure communications and manage digital certificates. It ensures that entities can securely exchange information, authenticate identities, and establish trust through the use of asymmetric encryption, where a pair of keys (public and private) are utilized. PKI supports various security services such as authentication, data integrity, and non-repudiation, which are vital for secure online transactions and communications.

5 Must Know Facts For Your Next Test

1. PKI consists of hardware, software, policies, and procedures that are used to manage digital certificates and public-key encryption.
2. The core components of PKI include Registration Authorities (RAs), which assist in the verification of identity before issuing certificates, and Certificate Revocation Lists (CRLs), which list certificates that are no longer valid.
3. PKI supports secure communication protocols like SSL/TLS, which rely on certificates to establish secure connections over the internet.
4. With PKI, users can sign documents digitally, ensuring authenticity and integrity while providing proof of origin, making it essential for e-commerce and legal transactions.
5. PKI also provides mechanisms for revoking access when keys are compromised, maintaining the overall security of communications within a network.

Review Questions

• How does Public Key Infrastructure facilitate secure communication and authentication in online transactions?
  • Public Key Infrastructure facilitates secure communication by providing a framework that uses digital certificates and public key cryptography. When parties engage in online transactions, PKI allows them to verify each other's identities through digital certificates issued by trusted Certificate Authorities. This process ensures that the data exchanged remains confidential and that both parties can trust each other, preventing impersonation and fraud.
• Discuss the roles of Certificate Authorities and Registration Authorities in maintaining the integrity of Public Key Infrastructure.
  • Certificate Authorities (CAs) are pivotal in PKI as they issue digital certificates that authenticate identities by binding them to their public keys. Registration Authorities (RAs) play a complementary role by verifying the identities of individuals or organizations requesting certificates before they are issued. Together, CAs and RAs uphold the integrity of PKI by ensuring that only valid entities are granted access to the public key system, enhancing overall security.
• Evaluate the impact of Public Key Infrastructure on secure protocols like SSL/TLS and how it contributes to online security as a whole.
  • Public Key Infrastructure significantly enhances secure protocols like SSL/TLS by providing a reliable method for establishing encrypted connections between clients and servers. Through digital certificates issued by CAs, PKI enables users to verify server identities before exchanging sensitive information, such as credit card details. The ability to authenticate both parties and ensure data integrity creates a robust layer of trust in online communications, making PKI essential for secure internet usage.

Related terms

Digital Certificate: A digital certificate is an electronic document used to prove the ownership of a public key, allowing for secure communication and authentication in PKI.

Certificate Authority (CA): A Certificate Authority is a trusted entity that issues digital certificates, verifying the identity of the certificate holder and binding them to their public key.

Asymmetric Cryptography: Asymmetric cryptography is a type of encryption that uses a pair of keys—a public key for encryption and a private key for decryption—enabling secure communication over insecure channels.