Composability in quantum cryptography

Understand

In this article, we review several aspects of composability in the context of quantum cryptography.

• The first part is devoted to key distribution.
• We discuss the security criteria that a quantum key distribution protocol must fulfill to allow its safe use within a larger security application (e.g., for secure message transmission).
• To illustrate the practical use of composability, we show how to generate a continuous key stream by sequentially composing rounds of a quantum key distribution protocol.