Key exchange (also known as "key establishment") is any method in cryptography by which cryptographic keys are exchanged between users, allowing use of a cryptographic algorithm.
If sender and receiver wish to exchange encrypted messages, each must be equipped to encrypt messages to be sent and decrypt messages received. The nature of the equipping they require depends on the encryption technique they might use. If they use a code, both will require a copy of the same codebook. If they use a cipher, they will need appropriate keys. If the cipher is a symmetric key cipher, both will need a copy of the same key. If an asymmetric key cipher with the public/private key property, both will need the other's public key.
Read more about Key Exchange: The Key Exchange Problem, The Future
Famous quotes containing the words key and/or exchange:
“The key to the age may be this, or that, or the other, as the young orators describe; the key to all ages is—Imbecility: imbecility in the vast majority of men, at all times, and even in heroes, in all but certain eminent moments: victims of gravity, customs and fear. This gives force to the strong,—that the multitude have no habit of self-reliance or original action.”
—Ralph Waldo Emerson (1803–1882)
“I know nothing which life has to offer so satisfying as the profound good understanding, which can subsist, after much exchange of good offices, between two virtuous men, each of whom is sure of himself, and sure of his friend. It is a happiness which postpones all other gratifications, and makes politics, and commerce, and churches, cheap.”
—Ralph Waldo Emerson (1803–1882)