Asymmetric encryption, also known as public-key encryption, is a form of data encryption where the encryption key (also called the public key) and the corresponding decryption key (also called the private key) are different. A message encrypted with the public key can be decrypted only with the corresponding private key. The public key and the private key are related mathematically, but it is computationally infeasible to derive the private key from the public key. Therefore, a recipient could distribute the public key widely. Anyone can use the public key to encrypt messages for the recipient and only the recipient can decrypt them.
A public-key encryption algorithm requires a trapdoor one-way function, i.e., a function that is easy to compute but hard to invert unless one knows some secret trapdoor (i.e., the private key). Existing public-key encryption algorithms are based on computational problems in number theory.
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