What is public key cryptography?
It is a modern branch of cryptography in which algorithms employ a pair of keys (a public key and a private key) and use a different component of the pair for different steps of the algorithm. For encryption, when A wants to ensure confidentiality for data it sends to B, it encrypts the data with a public key provided by B. Only B has the matching private key that is needed to decrypt the data. For signature, when A wants to ensure data integrity or provide authentication for data it sends to B, it uses its private key to sign the data (i.e., create a digital signature based on the data). To verify the signature, B uses the matching public key that A has provided. In order to ascertain a user’s public key is valid, the public key and relevant information (e.g. name, organization, email address, etc) of the user can be put together and digitally signed (endorsed) by a trusted Certification Authority (CA). The resulting digital document is known as a digital certificate.
Public Key Cryptography is a method for securely exchanging messages, based on assigning two complimentary keys (one public, one private) to the individuals involved in a transaction. Public Key Cryptography is based on the science of encryption, the mathematical scrambling and unscrambling of messages. To better understand Public Key Cryptography, it is useful to compare it to an alternative method of sending messages, Single Key Cryptography.
Public Key Cryptography is a method for securely exchanging messages, based on assigning two complimentary keys (one public, one private) to the individuals involved in a transaction. Public Key Cryptography is based on the science of encryption, the mathematical scrambling and unscrambling of messages.
