What is PKI?

Public Key Infrastructure (PKI) is a comprehensive framework that enables secure electronic communication and data exchange over networks, particularly the internet. It involves the use of cryptographic techniques to ensure the confidentiality, integrity, and authenticity of digital communications. Here are the key components and functions of PKI:

Components of PKI

1. Certificate Authority (CA):

   • The CA is a trusted entity responsible for issuing, storing, and signing digital certificates. It validates the identity of entities (individuals, organizations, or devices) and binds their public keys to their identities through these certificates[1][2][3][7].

2. Registration Authority (RA):

   • The RA acts as a verifier for the CA. It checks the credentials of entities requesting digital certificates and ensures their legitimacy before the CA issues the certificates[1][2][7].

3. Digital Certificates:

   • These are electronic documents that serve as "passports" for entities in the digital world. They contain the public key of the entity and are used to verify the identity of the certificate holder[2][4][7].

4. Public and Private Keys:

   • PKI uses a pair of cryptographic keys: a public key, which is shared openly, and a private key, which is kept secret. The public key is used to encrypt data, while the private key is used to decrypt it[5][6][7].

5. Certificate Repository:

   • A secure storage location where digital certificates and their associated metadata are stored and managed[1][4].

6. Certificate Revocation List (CRL) and Online Certificate Status Protocol (OCSP):

   • These mechanisms are used to manage and check the validity of certificates, ensuring that revoked or expired certificates are not used[8].

Functions of PKI

1. Encryption:

   • PKI enables the encryption of data to ensure that it remains confidential during transmission. Only the intended recipient, who possesses the corresponding private key, can decrypt the data[2][5][7].

2. Authentication:

   • By using digital certificates, PKI verifies the identity of entities involved in communication. This ensures that the parties are who they claim to be, preventing...