[liberationtech] Quantum computation & communication

[Gregory Foster]

After reading Assange, et. al.'s "Cypherpunks: Freedom and the Future of 
the Internet", wherein classical encryption is presented as a panacea 
for ensuring privacy in an age of mass surveillance, I found the 
following article succinct in questioning the long-term viability of 
that narrative (or at least insisting on some qualifications).  Quantum 
computation and communication is still a long distance away, but this 
article provides the outlines of how that technology will be used (and 
abused) by the institutions that will be able to afford it.

Aerospace & Defense News (Dec 19) - "Army Researchers Seek Secure 
Quantum Communications":
http://www.asdnews.com/news-46753/Army_Researchers_Seek_Secure_Quantum_Communications.htm

> For the U.S. Army, a secure quantum communications network is a 
> technology investment worth making. Meyers said physicists around the 
> world are pursuing quantum teleportation research.
>
> "One day we will have communication over worldwide distances with 
> quantum repeaters as mediators at nodes in between," Meyers said. 
> "We'll be able to teleport information globally. What we'll have is 
> tamper-resistant security."
>
> Cyber-security is a major concern for military and civilian sectors.
>
> "This is important," he said. "The greatest potential that a quantum 
> communications network holds for the Army is secure communications."
>
> As quantum computing takes hold in the coming decades, the potential 
> for hacking exponentially increases.
>
> "Quantum computers will be able to easily decrypt communications that 
> are currently secure," Meyers said. "We're talking decryption in 
> seconds instead of years. That's one reason why it's vital for us to 
> explore quantum encryption."


To understand the assertion that a sufficiently large quantum computer 
can (hypothetically) decrypt classically encrypted communications---from 
any time---see:
http://en.wikipedia.org/wiki/Shor's_algorithm

Will the economic effects of Moore's Law apply to quantum computers, 
facilitating the mass distribution and use of this technology for 
popular quantum cryptography?  Probably not for some period of time, a 
time which may recapitulate the big iron power dynamics of the mainframe 
priesthood.  It is that interim time period when there is likely to be a 
disparity in access to quantum computation that gives me pause.

However, in researching this post I was happy to learn that this threat 
is understood and research is underway into post-Quantum cryptography, 
which looks like it can be implemented on classical computers.  So 
predictable future problems may be mitigated by avoiding reliance on 
particular cryptographic techniques that are known to be breakable by 
quantum computers, such as the RSA algorithm used by many contemporary 
public-key cryptography systems:
http://en.wikipedia.org/wiki/Post-quantum_cryptography

I'll readily admit that I am about out of my depth here and welcome 
corrections and clarifications.  If we see this probability emerging, 
then it seems like liberationtechnicians should be advocating review and 
redesign of the algorithms used in popular public-key cryptosystems.

HT @ASDNewsCom via @MrKoot:
http://twitter.com/ASDNewscom/status/281018815276539904

gf

-- 
Gregory Foster || gfoster at entersection.org
@gregoryfoster <> http://entersection.com/