Ephemeral key
Encyclopedia
A cryptographic
key
is called ephemeral if it is generated for each execution of a key establishment process. In some cases ephemeral keys are used more than once, within a single session (e.g., in broadcast applications) where the sender generates only one ephemeral key pair per message and the private key is combined separately with each recipient's public key. Contrast with a static key
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Cryptography
Cryptography is the practice and study of techniques for secure communication in the presence of third parties...
key
Key (cryptography)
In cryptography, a key is a piece of information that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the particular transformation of plaintext into ciphertext, or vice versa...
is called ephemeral if it is generated for each execution of a key establishment process. In some cases ephemeral keys are used more than once, within a single session (e.g., in broadcast applications) where the sender generates only one ephemeral key pair per message and the private key is combined separately with each recipient's public key. Contrast with a static key
Static key
A cryptographic key is called static if it is intended for use for a relatively long period of time and is typically intended for use in many instances of a cryptographic key establishment scheme. Contrast with an ephemeral key.-See also:...
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External links
- Recommendation for Key Management — Part 1: general, NIST Special Publication 800-57
- NIST Cryptographic Toolkit