#### Answer Description

PKI, or Public-Key-Infrastructure uses asymmetric encryption. There is a public key, and a private key, anything encrypted with a key can only be decrypted with the opposing key.

#### Wikipedia

Public-key cryptography, or asymmetric cryptography, is a cryptographic system that uses pairs of keys: public keys which may be disseminated widely, and private keys which are known only to the owner. The generation of such keys depends on cryptographic algorithms based on mathematical problems to produce one-way functions. Effective security only requires keeping the private key private; the public key can be openly distributed without compromising security.In such a system, any person can encrypt a …

Public-key cryptography - Wikipedia, the free encyclopedia