Quantum Information Processing, Vol. 5, No. 2, April 2006 (© 2006)
and Daniel Lidar
Received January 24, 2006; accepted January 26, 2006; Published online March 29, 2006
When quantum communication networks proliferate they will likely be subject to a
new type of attack: by hackers, virus makers, and other malicious intruders. Here we
introduce the concept of “quantum malware” to describe such human-made intru-
sions. We offer a simple solution for storage of quantum information in a manner,
which protects quantum networks from quantum malware. This solution involves
swapping the quantum information at random times between the network and iso-
lated, distributed ancillas. It applies to arbitrary attack types, provided the pro-
tective operations are themselves not compromised.
KEY WORDS: Quantum malware; quantum cryptography; quantum commu-
nication; quantum computation; decoherence.
PAC S : 03.67.Hk; 03.67.-a; 03.67.Dd; 05.30.-d; 03.67.Pp.
Quantum information processing (QIP) offers unprecedented advantages
compared to its classical counterpart.
Quantum communication is mov-
ing from laboratory prototypes into real-life applications. For example,
quantum communication networks (“quantum internet”
been completed, and even commercialized.
Efforts to protect quan-
tum information ﬂowing through such networks have so far focused on
environmental (decoherence) and cryptographic (eavesdropping) “attacks”.
Quantum error correction has been developed to overcome these distur-
Malware (a portmanteau of “malicious software”), familiar from clas-
sical information networks, is any software developed for the purpose of
Departments of Chemistry, Electrical Engineering-Systems, and Physics, University of
Southern California, Los Angeles, CA 90089, USA.
To whom correspondence should be addressed. E-mail: firstname.lastname@example.org
1570-0755/06/0400-0069/0 © 2006 Springer Science+Business Media, Inc.