Explain the technique used in the asymmetric Key Cryptography.
Asymmetric or public-key cryptography be different from conventional cryptography in which key material is bound to a single user. This key material is divided in two components:
- A private key, to that only the user has access, and
- A public key that may be published or distributed on request.
Each key makes a function used to transform text. The private key makes a private transformation function and the public key makes a public transformation function. The functions are inversely associated, that is, if one function is utilized to encrypt a message, another is used to decrypt the message. The order wherein the transformation functions are invoked is irrelevant. See that the key material is used to produce the transformation functions, the meaning as private key and public key not only reference the key values, although also the transformation functions. For illustration, the phrase, ''the message is encrypted by using the message recipient's public key'', implies the recipient's public key transformation function is invoked by using the recipient's public key value and the message like inputs, and a cipher text representation of the message is produced as output.
The advantage of a public-key system is as two users can communicate securely without exchanging secret keys. For illustration, assume an originator requires sending a message to a recipient, and secrecy is needed for the message. The originator encrypts the message by using the recipient's public key. Merely the recipient's private key can be utilized to decrypt the message. This is because of the computational infeasibility of inverting the public key transformation function. Conversely, without the recipient's private key, this is computationally infeasible for the interceptor to transform cipher text in its original plain text.