01/2018
VOL. 61 NO. 01
Practice
46 Network Applications Are Interactive
The network era requires
new models, with interactions
instead of algorithms.
By Antony Alappatt
54 Abstracting the Geniuses Away
from Failure Testing
Ordinary users need tools
that automate the selection
of custom-tailored faults to inject.
By Peter Alvaro and Severine Tymon
62 Cache Me If You Can
Building a decentralized
Web-delivery model.
By Jacob Loveless
Articles’ development led by
queue.acm.org
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Contributed Articles
70 Popularity Spikes Hurt Future
Chances for Viral Propagation
of Protomemes
Once a meme gets popular, it will
have to evolve to keep being popular.
By Michele Coscia
78 Decentralized Blockchain-Based
Electronic Marketplaces
In a decentralized marketplace,
buyers and sellers transact
directly, without manipulation
by intermediary platforms.
By Hemang Subramanian
Watch the author discuss
his work in this exclusive
Communications video.
https://cacm.acm.org/
videos/decentralized-blockchain-based-e-marketplaces
Review Articles
86 Information Hiding:
Challenges for Forensic Experts
The practice of hiding ill-gotten data
in digital objects is rising among
cyber thieves. New initiatives
serve to educate, train, and
thwart these activities.
By Wojciech Mazurczyk
and Steffen Wendzel
Research Highlights
96 Technical Perspective
Moving Spectrum
By David C. Parkes
97 Deep Optimization
for Spectrum Repacking
By Neil Newman, Alexandre Fréchette,
and Kevin Leyton-Brown
105 Technical Perspective
Can High Performance
Be Portable?
By Manuel Chakravarty
106 Halide: Decoupling Algorithms
from Schedules for High-Performance
Image Processing
By Jonathan Ragan-Kelley,
Andrew Adams, Dillon Sharlet,
Connelly Barnes, Sylvain Paris,
Marc Levoy, Saman Amarasinghe,
and Frédo Durand
Watch the authors discuss
their work in this exclusive
Communications video.
https://cacm.acm.org/
videos/information-hiding 54 78
About the Cover:
Blockchain technologies
are positioned to transform
the business world,
connecting buyers and
sellers and keeping records
of their digital transactions
clean and secure. This
month’s cover story (p. 78)
explores the advantages
of decentralized
e-marketplaces using
blockchain technology
as the facilitator. Cover
illustration by Spooky
Pooka at Debut Art.