Symmetric and Asymmetric Cryptography
Symmetric Cryptography
- Single Key: Uses a single key for both encryption and decryption.
- Speed: Generally faster due to simpler algorithms.
- Key Distribution: Requires secure key exchange, which can be challenging.
- Consider Jane and Tim want to communicate securely.
- They use a shared secret key to encrypt and decrypt messages.
- If a hacker obtains this key, they can read all communications.
Asymmetric Cryptography
- Key Pair: Involves a public key (for encryption) and a private key (for decryption).
- Security: Solves the key distribution problem, as the public key can be shared openly.
- Speed: Slower due to complex mathematical operations.
- Jane wants to send Tim a secure message.
- She encrypts it using Tim's public key.
- Only Tim can decrypt it with his private key, ensuring confidentiality.
Symmetric cryptography is ideal for large data volumes due to its speed, while asymmetric cryptography is used for secure key exchange and digital signatures.
The Role of Digital Certificates
- Definition: Digital certificates are electronic documents that bind a public key to an identity (e.g., a person or organization).
- Issuance: Issued by Certificate Authorities (CAs), which verify the certificate holder's identity.
