Computing Now Exclusive Content — January 2010

News Archive

July 2012

Gig.U Project Aims for an Ultrafast US Internet

June 2012

Bringing Location and Navigation Technology Indoors

May 2012

Plans Under Way for Roaming between Cellular and Wi-Fi Networks

Encryption System Flaw Threatens Internet Security

April 2012

For Business Intelligence, the Trend Is Location, Location, Location

Corpus Linguistics Keep Up-to-Date with Language

March 2012

Are Tomorrow's Firewalls Finally Here Today?

February 2012

Spatial Humanities Brings History to Life

December 2011

Could Hackers Take Your Car for a Ride?

November 2011

What to Do about Supercookies?

October 2011

Lights, Camera, Virtual Moviemaking

September 2011

Revolutionizing Wall Street with News Analytics

August 2011

Growing Network-Encryption Use Puts Systems at Risk

New Project Could Promote Semantic Web

July 2011

FBI Employs New Botnet Eradication Tactics

Google and Twitter "Like" Social Indexing

June 2011

Computing Commodities Market in the Cloud

May 2011

Intel Chips Step up to 3D

Apple Programming Error Raises Privacy Concerns

Thunderbolt Promises Lightning Speed

April 2011

Industrial Control Systems Face More Security Challenges

Microsoft Effort Takes Down Massive Botnet

March 2011

IP Addresses Getting Security Upgrade

February 2011

Studios Agree on DRM Infrastructure

January 2011

New Web Protocol Promises to Reduce Browser Latency

To Be or NAT to Be?

December 2010

Intel Gets inside the Helmet

Tuning Body-to-Body Networks with RF Modeling

November 2010

New Wi-Fi Spec Simplifies Connectivity

Expanded Top-Level Domains Could Spur Internet Real Estate Boom

October 2010

New Weapon in War on Botnets

September 2010

Content-Centered Internet Architecture Gets a Boost

Gesturing Going Mainstream

August 2010

Is Context-Aware Computing Ready for the Limelight?

Flexible Routing in the Cloud

Signal Congestion Rejuvenates Interest in Cell Paging-Channel Protocol

July 2010

New Protocol Improves Interaction among Networked Devices and Applications

Security for Domain Name System Takes a Big Step Forward

The ROADM to Smarter Optical Networking

Distributed Cache Goes Mainstream

June 2010

New Application Protects Mobile-Phone Passwords

WiGig Alliance Reveals Ultrafast Wireless Specification

Cognitive Radio Adds Intelligence to Wireless Technology

May 2010

New Product Uses Light Connections in Blade Server

April 2010

Browser Fingerprints Threaten Privacy

New Animation Technique Uses Motion Frequencies to Shake Trees

March 2010

Researchers Take Promising Approach to Chemical Computing

Screen-Capture Programming: What You See is What You Script

Research Project Sends Data Wirelessly at High Speeds via Light

February 2010

Faster Testing for Complex Software Systems

IEEE 802.1Qbg/h to Simplify Data Center Virtual LAN Management

Distributed Data-Analysis Approach Gains Popularity

Twitter Tweak Helps Haiti Relief Effort

January 2010

2010 Rings in Some Y2K-like Problems

Infrastructure Sensors Improve Home Monitoring

Internet Search Takes a Semantic Turn

December 2009

Phase-Change Memory Technology Moves toward Mass Production

IBM Crowdsources Translation Software

Digital Ants Promise New Security Paradigm

November 2009

Program Uses Mobile Technology to Help with Crises

More Cores Keep Power Down

White-Space Networking Goes Live

Mobile Web 2.0 Experiences Growing Pains

October 2009

More Spectrum Sought for Body Sensor Networks

Optics for Universal I/O and Speed

High-Performance Computing Adds Virtualization to the Mix

ICANN Accountability Goes Multinational

RFID Tags Chat Their Way to Energy Efficiency

September 2009

Delay-Tolerant Networks in Your Pocket

Flash Cookies Stir Privacy Concerns

Addressing the Challenge of Cloud-Computing Interoperability

Ephemeralizing the Web

August 2009

Bluetooth Speeds Up

Grids Get Closer

DCN Gets Ready for Production

The Sims Meet Science

Sexy Space Threat Comes to Mobile Phones

July 2009

WiGig Alliance Makes Push for HD Specification

New Dilemnas, Same Principles:
Changing Landscape Requires IT Ethics to Go Mainstream

Synthetic DNS Stirs Controversy:
Why Breaking Is a Good Thing

New Approach Fights Microchip Piracy

Technique Makes Strong Encryption Easier to Use

New Adobe Flash Streams Internet Directly to TVs

June 2009

Aging Satellites Spark GPS Concerns

The Changing World of Outsourcing

North American CS Enrollment Rises for First Time in Seven Years

Materials Breakthrough Could Eliminate Bootups

April 2009

Trusted Computing Shapes Self-Encrypting Drives

March 2009

Google, Publishers to Try New Advertising Methods

Siftables Offer New Interaction Model for Serious Games

Hulu Boxed In by Media Conglomerates

February 2009

Chips on Verge of Reaching 32 nm Nodes

Hathaway to Lead Cybersecurity Review

A Match Made in Heaven: Gaming Enters the Cloud

January 2009

Government Support Could Spell Big Year for Open Source

25 Reasons For Better Programming

Web Guide Turns Playstation 3 Consoles into Supercomputing Cluster

Flagbearers for Technology: Contemporary Techniques Showcase US Artifact and European Treasures

December 2008

.Tel TLD Debuts As New Way to Network

Science Exchange

November 2008

The Future is Reconfigurable

Infrastructure Sensors Improve Home Monitoring

by George Lawton

A University of Washington researcher is developing a system to make it easier for individuals and companies monitor "home" activity by using strategically placed sensors on air, water, gas, and electrical infrastructure. Assistant professor Shwetak Patel calls his approach infrastructure-mediated sensing (IMS).

Patel expects IMS to be more cost effective and less labor intensive than other activity-sensing platforms. Most of these have relied on a distributed, direct-sensing approach with many sensors distributed throughout a home or office. While the materials costs for each sensor might be relatively inexpensive, the installation and maintenance costs can be quite high.

In contrast, IMS uses a single sensor in a strategic place to measure pressure signals in air vents and waterlines as well as electrical signals in power lines. Machine-learning technologies correlate physical events such as turning on a light, flushing a toilet, or opening a door with different signals. According to Patel, IMS's primary goal is to reduce the economic, aesthetic, installation, and maintenance barriers to home monitoring by reducing the cost and complexity of deploying and maintaining and activity-sensing infrastructure.Patel said that in large volumes the water, pressure, and power sensors will cost as little as US$50 each.

Under the Hood: Event Detectors

The IMS Powerline Event Detection (PED) system uses an oscilloscope plugged into any outlet within a home to monitor the signals of devices turned on or off throughout the home. It can detect electrical events with 85–90 percent accuracy, using filters to classify the signals generated when devices are turned on or off and when they're running. Each home device generates a unique signal based on its electromagnetic properties and its location on the home network. The system uses the different locations of identical devices on the circuit to distinguish between them.

This approach is based on the observation of broadband transient noise that abruptly switched electrical loads produce and continuous electrical noise. Three classes of noise sources in homes are resistive loads such as light and heaters, inductive loads such as motors, and solid-state loads such as computer power supplies. Devices such as electrical switches generate transient noise when switched on and off but no continuous noise. Others, such as solid-state loads, generate continuous noise. The PED classifies these signals into events, which it logs onto a computer.

The IMS HydroSense is a pressure sensor that screws onto any unused water outlet. It consists of a standard faucet adaptor that's closed on one end. It can identify activity and flow through any home fixture such as toilets, faucets, and showers with 97.9 percent aggregate accuracy. The HydroSense tracks the pressure wave, called a waterhammer, generated when faucets are opened or closed. This wave travels throughout the home's water pipes and can be measured at any water outlet.

Patel has tested a third system for monitoring pressure gradients in a heating, ventilation, and air conditioning (HVAC) system, The system can detect the opening and closing of doors with 75–80 percent accuracy. It consists of a set of five pressure sensors attached to the surface of a single screen on the HVAC intake tube. As people move between rooms and doors open or close, they generate a unique signal across the five sensors.


Calibration and compound events pose the biggest challenge for all of these systems.

An installer must generate each event to be detected and record its time so that the system can calibrate the event with its unique signal. In an electrical system, this would involve turning on and off every light, fan, and appliance in the home. Calibrating the water system involves flushing every toilet and running every faucet. The HVAC system would need to track walking through and opening and closing all of the doors.

One limit of calibration is that it picks up only a particular use case. Mobile devices, such as laptops or vacuum cleaners, generate a different electrical signal when they’re plugged into different sockets. Faucets generate a slightly different water pressure signal when opened slowly or part way.

When multiple events affect the same infrastructure simultaneously, they generate a compound event in which the signals overlap and become more difficult to correlate with the individual constituents. This might happen, for example, when a light turns on at the same time as the refrigerator motor or a faucet starts running at the same time as a toilet is flushing. This is less with electrical systems because events occur over a much shorter time frame, but it could be a limitation in larger installations that attempt to track many people's activities.

A Granular Future

This technology promises to help drive both improve home automation and better electrical monitoring. Bill Ablondi, director of Home Systems and Energy Research at Parks Associates, said that consumers can reduce energy usage by 10–15 percent through better monitoring technologies. Parks Associates' surveys have found that 85 percent of consumers are willing to pay for energy monitors if they could help reduce their energy bills. But wide deployment would depend on such systems costing less than $200 for the whole house. 

There are many questions about whether monitoring systems would be sold directly to consumers or to utilities, which would give them away. Ablondi said that broadband Internet providers like Verizon are even looking at providing power monitoring and energy as a service. 

"As we migrate to the next generation of energy management solutions, the more granular data you can provide, the better. So technology like PED is likely to be beneficial," said Mareca Hatler, industry analyst with ON World. ON World predicts that home-area networks will increase worldwide from less than a million homes in 2009 to 20 million in 2013. Energy-management technology companies such as EnergyHub, Google, Greenbox, PowerMand, and Tendril are driving the market growth.

George Lawton is a freelance technology writer based in Monte Rio, California. Contact him at