Key signature A minor as each accidental may be notated explicitly as required, or the piece may be modal or atonal. An example is Bartók's Piano Sonata, which has no fixed key and is highly chromatic. If not bound by common practice conventions, microtones can also be notated in a key signature; which microtonal symbols are used depends on the system. The common practice period conventions are so firmly established that some musical notation programs have been unable to show nonstandard key signatures until recently. The use of a one-flat signature developed in the Medieval period, but signatures with more than one
Transient-key cryptography that a given piece of data has not changed since it was signed. But the similarities end there. In a traditional public key system, the public/private keypair is typically assigned to an individual, server, or organization. Data signed by a private key asserts that the signature came from the indicated source. Keypairs persist for years at a time, so the private component must be carefully guarded against disclosure; in a public-key system, anyone with access to a private key can counterfeit that person's digital signature. In transient-key systems, however, the keypair is assigned to a brief interval of time, not