Software → Security
Public-Key Cryptography
Cryptographic systems based on public/private key pairs for encryption, signatures, identity, and key exchange.
Motivation
Public-key cryptography solves the problem of secure communication and identity in open networks.
Where it fits
Public-Key Cryptography belongs to cryptography and security.
Mental model
A public key can be shared widely, while a private key remains secret. Together they enable encryption, signatures, and key exchange patterns.
Subconcepts
Public Key
The shareable half of an asymmetric key pair, used to verify signatures or encrypt data for the private-key holder.
Private Key
The secret half of an asymmetric key pair, used to decrypt data or create digital signatures.
Common mistakes
- Treating the public key as secret.
- Trusting a public key without verifying ownership.
Related concepts
Public-Key Cryptography connects to RSA, digital signature, certificate authority, TLS, and key exchange.