NIST logo  ‘Dead Time’ Limits Quantum Cryptography Speeds  For
Immediate Release: September 27, 2007  Bookmark and Share
Contact: Ben Stein  Quantum cryptography is potentially the most
secure method of sending encrypted information, but does it have
a speed limit? According to a new paper* by researchers at the
National Institute of Standards and Technology (NIST) and the
Joint Quantum Institute (JQI), technological and security issues
will stall maximum transmission rates at levels comparable to
that of a single broadband connection, such as a cable modem,
unless researchers reduce “dead times” in the detectors that
receive quantum-encrypted messages. The JQI is a research
partnership that includes NIST and the University of Maryland.
In quantum cryptography, a sender, usually designated Alice,
transmits single photons, or particles of light, encoding 0s and
1s to a recipient, “Bob.” The photons Bob receives and correctly
measures make up the secret “key” that is used to decode a
subsequent message. Becau