Public key cryptography is based on the conversion of information at sender end and then reconverting the information into its original form at the receiver end.

It is asymmetric kind of conversion because two different will be used for this conversion one public key and the private key.

The public key is used to encrypt the data while the private key is used to decrypt it into the original form.

Anyone with a copy of your public key can then encrypt information that only you can read. Even people you have never met.

It is computationally infeasible to deduce the private key from the public key. Anyone who has a public key can encrypt information but cannot decrypt it. Only the person who has the corresponding private key can decrypt the information.

The primary benefit of public key cryptography is that it allows people who have no preexisting security arrangement to exchange messages securely.

Because conventional cryptography was once the only available means for relaying secret information, the expense of secure channels and key distribution relegated its use only to those who could afford it, such as governments and large banks .

Public key encryption is the technological revolution that provides strong cryptography to the adult masses.

• Different keys are used for encryption and decryption.

• Each receiver possesses a unique decryption key, generally referred to as his private key.

• Receiver needs to publish an encryption key, referred to as his public key.

• Some assurance of the authenticity of a public key is needed in this scheme to avoid spoofing by adversary as the receiver.

• Encryption algorithm is complex enough to prohibit attacker from deducing the plaintext from the ciphertext and the encryption (public) key.

• Though private and public keys are related mathematically, it is not be feasible to calculate the private key from the public key.