Contents
What is PKI (Public Key Infrastructure)?
PKI stands for Public Key Infrastructure, and it is a mechanism used for secure communication and information exchange over a network. It is based on asymmetric encryption, which involves the use of two different keys, a public key, and a private key.
The main purpose of PKI is to ensure confidentiality, integrity, and authenticity in online transactions and communication. It provides a framework for managing digital certificates, which are used to authenticate the identity of users and secure the transmission of sensitive data.
Components of PKI:
1. Certificate Authority (CA): The CA is a trusted third-party organization responsible for issuing and managing digital certificates. It verifies the identity of individuals, organizations, or devices and issues a digital certificate that contains the public key and other relevant information.
2. Registration Authority (RA): Sometimes, the CA delegates certain tasks to a Registration Authority. The RA acts as an intermediary between the CA and the users, assisting in the verification process and handling certificate requests.
3. Public Key: The public key is made available to the public and is used for encryption and verifying digital signatures. It can be freely distributed and is used by others to encrypt messages intended for the key owner.
4. Private Key: The private key is kept confidential and securely stored by the key owner. It is used for decrypting messages received and creating digital signatures to authenticate the sender’s identity.
5. Digital Certificates: Digital certificates are electronic documents issued by the CA that bind the user’s identity to their public key. The certificates contain information such as the user’s name, public key, expiry date, and the CA’s digital signature. They are used to establish trust and verify the authenticity of the public key.
How PKI works:
1. Generating Keys: A user generates a pair of cryptographic keys – a public key and a private key. The private key is kept securely, while the public key is shared.
2. Requesting a Certificate: The user requests a digital certificate from the CA, providing necessary identification information.
3. Verification: The CA verifies the user’s identity using various methods such as physical documentation or domain ownership verification.
4. Issuing the Certificate: Upon successful verification, the CA issues a digital certificate containing the user’s public key and other relevant information. The certificate is digitally signed by the CA.
5. Certificate Distribution: The user distributes the digital certificate to the intended recipients. This allows others to encrypt messages using the user’s public key and verify their digital signatures.
6. Encryption and Decryption: When sending a message, the sender encrypts it using the recipient’s public key. The recipient then decrypts the message using their private key.
7. Digital Signatures: To authenticate the sender’s identity and ensure message integrity, the sender can digitally sign the message using their private key. The recipient can verify the signature using the sender’s public key.
PKI has become a crucial technology for establishing secure communication channels, protecting sensitive data, and ensuring the integrity of digital transactions. It forms the foundation for various security protocols and technologies such as secure email, SSL/TLS for secure web browsing, and digital signatures for document verification.
Reference Articles
Read also
[Google Chrome] The definitive solution for right-click translations that no longer come up.