Cryptography cryptography security encryption

What is RSA?

Definition

RSA (Rivest-Shamir-Adleman) is an asymmetric encryption algorithm that uses a pair of keys: a public key for encryption and a private key for decryption. Its security is based on the mathematical difficulty of factoring large prime numbers.

Why It Matters

RSA is the foundation of SSL/TLS handshakes, SSH authentication, digital signatures, and email encryption (PGP/GPG). While not used for bulk data encryption (AES is faster), RSA secures the key exchange that establishes encrypted connections.

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