05/2014
VOL. 57 NO. 05
Practice
Contributed Articles
Review Articles
52
44 The NSA and Snowden:
Securing the All-Seeing Eye
How good security at the NSA
could have stopped him.
By Bob Toxen
52 A Primer on Provenance
Better understanding data requires
tracking its history and context.
By Lucian Carata, Sherif Akoush,
Nikilesh Balakrishnan,
Thomas Bytheway, Ripduman Sohan,
Margo Seltzer, and Andy Hopper
61 Don’t Settle for Eventual Consistency
Stronger properties for low-latency
geo-replicated storage.
By Wyatt Lloyd, Michael J. Freedman,
Michael Kaminsky, and David G. Andersen
IMAGES BY ANDRIJ BORYS ASSOCIATES; ILLUS TRATION BY EUGENE KOSTSOV
Articles’ development led by
queue.acm.org
70
98
70 Cloud Security: A Gathering Storm
Users’ trust in cloud systems
is undermined by the lack
of transparency in existing
security policies.
By Mihir Nanavati, Patrick Colp,
Bill Aiello, and Andrew Warfield
80 Reducing the Software Value Gap
How to cope with the growing
demand for software solutions
at no extra cost.
By Shimeon Pass and Boaz Ronen
88 The Community Source Approach
to Software Development
and the Kuali Experience
Participating educational
institutions get a much more
cost-effective result compared to the
commercial off-the-shelf alternative.
By Manlu Liu, Sean Hansen,
and Qiang Tu
98 Understanding the Empirical
Hardness of NP-Complete Problems
Using machine learning
to predict algorithm runtime.
By Kevin Leyton-Brown, Holger H. Hoos,
Frank Hutter, and Lin Xu
Research Highlights
109 Technical Perspective
The Interplay of Neuroscience
and Cryptography
By Ari Juels and Bonnie Wong
110 Neuroscience Meets Cryptography:
Crypto Primitives Secure
Against Rubber Hose Attacks
By Hristo Bojinov, Daniel Sanchez,
Paul Reber, Dan Boneh,
and Patrick Lincoln
About the Cover:
Much has been written
about Edward Snowden,
the former National
Security Agency
subcontractor who shot to
global notoriety by leaking
top-secret data about
the agency’s surveillance
activities. While media
outlets continue to debate
why he did it, this month’s
cover story (p. 44) traces
how he did it, pointing out
the glaring weaknesses in
the NSA’s own security practices. Cover illustration by
Peter Crowther Associates.