In cryptography, a revolutionary new method of encryption that does not require the message’s receiver to have received the decoding key in a separate transmission. The need to send the key, which is required to decode the message, is the chief vulnerability of previous encryption techniques.
In public-key cryptography, there are two keys: a public one and a private one. The public key is used for encryption, and the private key is used for decryption. If John wants to receive a private message from Alice, John sends his public key to Alice; Alice then uses the key to encrypt the message. Alice sends the message to John. Anyone trying to intercept the message en route would find that it is mere gibberish. When John receives the message, he uses his private key to decode it. Because John never sends his private key anywhere or gives it to anyone, he can be certain that the message is secure. Public key cryptography places into the hands of individuals a level of security that was formerly available only to the top levels of government security agencies.
Technipages Explains Public Key Cryptography
Public key cryptography also called Asymmetric Key cryptography, is a system of encryption which is based on the use of two virtual keys, the private key, and the public key. The private key is used to decrypt a message while the public key is used to encrypt the message. In this model, once a message is encrypted by the public key, only the private key can decrypt the message. Just as the name of the key depicts, the private key is meant to be private so that only the handler of the key can access the message, unlike the public key which can be encrypted by anyone.
The keys are virtual keys, and the private and public keys are large numerical values used to encrypt and decrypt data. The keys are produced by a trusted authority trusted by both parties. The private key is usually held by the generator of the key pair, while the public key, to anyone who wants to send data.
In 1977, public key cryptography was published by Whitfield-Diffie and Martin Hellman, but it was initially formulated by James Ellis. But even neither of them could devise applications of these in a practical world. Rivest-Shamir-Adleman was the first to publish a working public key cryptography system.
Common Uses of Public Key Cryptography
- Public key cryptography is a modern cryptographic process for communicating securely without having previously agreed upon the secret key
- In public key cryptography, it utilizes a pair of keys to establish secure communication.
- Public key cryptography brings major security technologies to the desktop in the Windows 2000 environment.
Common Misuses of Public Key Cryptography
- Public key cryptography doesn’t allow for non-repudiation so the sender can deny sending a message
- In public key cryptography, when a private key is lost, there are other ways to decrypt the message