Computing Now Exclusive Content — November 2009

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

White-Space Networking Goes Live

by George Lawton

Under an experimental license from the US Federal Communications Commission (FCC), Spectrum Bridge launched the first US wireless broadband network using empty airwaves ("white spaces") in the broadcast television spectrum, which emerged in the transition to digital TV. The white-space network is providing broadband Internet services to the unincorporated community of Claudville, Virginia, and could pave the way for broader adoption of the technology — across empty TV spectrum initially and a much wider range eventually.

The TDF Foundation funded the network, which uses software and webcams from Microsoft, PCs from Dell, and Spectrum Bridge networking equipment. It was designed to show the superior range and penetration of TV's lower frequencies compared to Wi-Fi, noted Peter Stanforth, Spectrum Bridge CTO. Wi-Fi operates in the much higher ISM (industry, science, medicine) radio spectrum (2400–2450 MHz). TV's lower frequency (76–600 MHz) offers substantially better range and penetration, which Stanforth said makes it ideal for providing last-mile Internet connectivity in rural areas. It also offers good penetration between walls and floors for local networking.

TDF had previously built a community networking center in Claudville with a high-speed Internet connection. In the white-space deployment, Spectrum Bridge provided the radios to link three remote base stations, each with local Wi-Fi access.

Unlicensing White Space

Michael Calabrese, vice president of the New American Foundation public policy institute, first proposed the idea of white space for unlicensed communication in 2001. Proponents say it will help open the airwaves for better broadband connectivity and provide services that would compete with those of cable TV and telephone companies, thereby lowering pricing and spurring innovation.

Opponents — including the National Associations of Broadcasters (NAB) and wireless-microphone vendor Shure — are concerned that white-space networking could impair broadcasters and wireless microphone users that are already using this spectrum.

NAB spokesperson Kristopher Jones said, "The NAB has had concerns about white-space networking from the outset. Our business is based on delivering an interference-free pristine picture. If a consumer is not getting a good picture, they will change the channel." Jones said the difficulty is that the white-space devices would be unlicensed. "When you have a device that's unlicensed and unmonitored," he explained, "if it does cause problems, it's difficult if not impossible to track down the offending devices."

The FCC is in the final stages of drafting plans to manage the use of white space. It's looking at two components for eliminating interference: sensing chips that automatically cut off when they detect a TV or microphone transmission and a database for looking up empty channels in an area before transmitting.

The FCC is proposing to limit the maximum power of white space devices to 4 watts, which is equivalent to Wi-Fi. But the propagation characteristics of the lower frequencies provides about four times the range of the ISM band, said Stanforth.

Each TV channel occupies 6 MHz of spectrum, but the channel space is not contiguous. There are many large blocks of channels with substantial gaps between them. For example, channels 5 and 6 occupy the 76–88 MHz range, followed by a 66 MHz gap before channels 7–13 in the 174–216 MHz range.

Rural areas have many vacancies, whereas cities have only a few. In total, TV has far less available white space than the ISM band, particularly in crowded markets.

Dawn of the Frequency API

One challenge to white-space networking has been determining who's using what spectrum in a particular location. The FCC maintains a database but not in a form that makes it easy to find information in real time.

Spectrum Bridge developed database technology that adds a metadata layer to the FCC database to simplify the search for available spectrum in an area. The company has also developed an API that lets a device automatically query the database. This combination can help a receiver determine whether operating in a particular frequency range is liable to interrupt a local TV station.

Under the FCC's proposal, when a radio is installed, it must automatically determine its location using GPS or have a technician do so. The white-space device would use the radio location and database to identify free channels. The devices would check the database at least once every 24 hours. In some cases, the devices could be forced to recheck the database whenever another permitted user begins to use the frequency.

"Once you build this kind of white-space infrastructure," Stanforth said, "and you have a radio with a dynamic range that can query a database, there's no reason that you would be limited to TV white space. There's quite a lot of other spectrum defined as secondary market spectrum, some of which is free today."

A bill introduced in the US Congress in July, the Radio Spectrum Inventory Act, would open white space across the entire unused spectrum for unlicensed operation.

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