Fighting malware and spam

Public Key Cryptography

Encryption technique using public and private keys

The public key method of cryptography is a fairly high-security means of encryption, which is also widely available, and is used by many security professionals to ensure the security and integrity of their data and communications.

In PKI, each user has a public key and a private key; the public key can be given away freely, even published on a website, and can be used to encrypt data in such a way that only the holder of the private key (and the associated password) can decrypt it. Private keys can also be used to create certificates assuring the authenticity of systems and web pages, which can be verified against the associated public key - public keys can in turn be validated by a central authority and a chain of key signing (the 'web of trust').

Popular implementations of PKI include PGP, and the compatible freeware equivalent GPG.