## Public-key Cryptography## From CryptoDox, The Online Encyclopedia on Cryptography and Information SecurityAlso known as This is a form of cryptography that allows secure communication without having any prior knowledge or access to the secret key. This is achieved by using a pair of mathematically related cryptographic keys which are known as private and public keys. The sender uses the recipients public key to secure the data. Upon receiving the data, the recipient decrypts it uses the private key. The private key as the name suggests must not be shared with anyone. The public key on the other hand, as the name suggests, should be available freely to everyone to ensure that they can communicate securely with the recipient. The first published cryptographic system that did not require a shared key was published by Whitfield Diffie and Martin Hellman in 1976, now called Diffie-Hellman key agreement.
## Algorithms- RSA
- Diffie-Hellman
- DSS (Digital Signature Standard), which incorporates the Digital Signature Algorithm
- ElGamal
- FIPS 201 PIV (Personal Identity Verification of Federal Employees and Contractors)
- Microsoft CAPI
Examples of protocols using asymmetric key algorithms include: - GPG an implementation of OpenPGP
- IKE
- PGP
- ssh
- Secure Socket Layer (SSL) now implemented as an IETF standard -- TLS
- SILC
## See Also- PKI - Public Key Infrastructure
## External References |