More on LightSquared

February 21, 2012

A couple of days ago, I posted a note here about the FCC’s decision to suspend indefinitely its provisional approval of the broadband wireless service proposed by LightSquared, because of it potential interference with the operation of the Global Positioning System [GPS].  LightSquared has consistently claimed that interference was the fault of the GPS device manufacturers, because their designs did not include adequate protection against signals on nearby frequencies.

Ars Technica has a new article discussing the situation in more detail.  The article largely comes to the same conclusion I have: that, while there may be some truth in LightSquared’s claim, the disruption of the existing GPS ecosystem is too big a price to pay for the benefits the proposed system would bring.

FCC Says No to LightSquared

February 19, 2012

Last summer, I wrote here a couple of times about a controversy surrounding a proposed new broadband wireless Internet service, to be provided by a company called LightSquared.  The central issue was the possibility that the new system would cause interference problems with the Global Positioning System [GPS].  The new service was planned to use a slice of the frequency spectrum, originally intended for satellite telephone service, that is just below the frequencies used by GPS.  When the spectrum licenses were originally acquired by SkyTerra Communications, a predecessor company to LightSquared, the plan was to make connections primarily with satellite links, with some small ground stations to fill in holes in the coverage. The controversy has come about because LightSquared persuaded the Federal Communications Commission[FCC] to amend its license to allow a service based almost entirely on a network of 40,000 ground transmitters.

As I noted in my earlier posts, there have been a variety of studies proposed and carried out to asses the potential for interference.  The results have suggested that the interference problem is real, and might have a significant adverse effect on GPS users.  Now, according to articles at Ars Technica and the New York Times, the FCC has indefinitely suspended its provisional approval of the LightSquared system, following the release of a final report from the National Telecommunications and Information Administration, part of the Department of Commerce.

The Federal Communications Commission (FCC) said today that it will not approve LightSquared’s proposal to build a national 4G-LTE network, after testing showed that the network would interfere with most existing GPS devices.

The decision came swiftly after the National Telecommunications and Information Administration (NTIA) today warned the FCC that “LightSquared’s proposed mobile broadband network will impact GPS services and that there is no practical way to mitigate the potential interference at this time.”

LightSquared claims that the interference is primarily due to the poor design of existing GPS equipment, which does not adequately reject signals on nearby frequencies.  There probably is at least some truth in this; originally, the spectrum LightSquared proposed using was slated to be used for satellite-based services.  Like the signals from GPS satellites, these would have been relatively weak.  But the ground stations LightSquared proposed as part of its system would have produced signals about a billion times as strong as the GPS signals, making adequate filtering very difficult.

The company says that it still hopes to reach a mutually acceptable solution with the FCC, which has issued a request for comments on the NTIA letter.   I hope that they succeed, because the new broadband capacity would be valuable, but messing up the GPS, which is used for so many purposes, is a price too high.

Intel to Offer Transactional Memory

February 18, 2012

Back in September of last year, I wrote about the transactional memory hardware being used by IBM in the new Sequoia super-computer it is building for the Lawrence Livermore National Laboratory.  The technology is expected to make software development for parallel processing easier.  Now, according to an article at Ars Technica, Intel plans to bring transactional memory support to mainstream products, beginning with its Haswell chips, due to ship sometime next year.  In a blog post announcing the feature, which it calls TSX (Transaction Synchronization Extensions), Intel’s James Reinders explains the basic idea of TSX:

In a nutshell, Intel TSX provides a set of instruction set extensions that allow programmers to specify regions of code for transactional synchronization. Programmers can use these extensions to achieve the performance of fine-grain locking while actually programming using coarse-grain locks.

The post also gives an overview of how the new capabilities can be used.  TSX has two application interfaces.  The first, called Hardware Lock Elision [HLE] is intended to make easier  the porting of existing code, which may use locks.  It also makes it possible to have code that will work correctly on both older processors (which don’t support transactional memory) and Haswell.   The second, Restricted Transactional Memory [RTM], is intended primarily for new development, and provides more flexible structuring of transactions than is possible with HLE.

Although the idea of atomic transactions should be familiar to anyone who has developed relational data base applications, transactional memory is still pretty new.  The TSX capabilities that Intel will provide are very low-level (close to the hardware) functions.  Development of higher-level development tools that can take advantage of facilities like TSX is still in the early stages, but the work has started.  I think the development holds a lot of promise for easier development of software that can use highly parallel hardware effectively.

Update Monday, 20 February, 10:51 EST

Corrected the chip name to ‘Haswell’, rather than ‘Haskell’.  Thanks to Jim Cownie for the correction.

Firefox, Thunderbird Get Security Updates

February 18, 2012

The Mozilla organization has released new versions of its Firefox browser and Thunderbird E-mail client; in both cases the new version number is 10.0.2.  The updates fix a critical security vulnerability in the library used to render PNG graphics.   More information is available in the Release Notes for Thunderbird and for Firefox.

I recommend upgrading your system as soon as you conveniently can.  You can get the new version via the built-in update mechanism (Help / About/ Check for Updates), or you can download a complete installation package for Firefox or Thunderbird, ina variety of (human) languages.

Critical Updates for Java

February 16, 2012

Oracle has released its quarterly security fixes for Java.  The new Version 6 Update 31, addresses 14 identified security vulnerabilities; at least one of these is extremely serious, because it can be exploited remotely without a login.  (There is also a Version 7 Update 3 available for developers, with the same fixes.)  Further information is available in the Critical Patch Update Advisory.

The new version is available for almost all platforms: Linux, Windows, and Solaris.  Apple supplies its own versions of Java for Mac OS X; there is usually a time lag of at least a few days after Oracle releases a new version before an updated Mac version is available

Because of the security content of this release, if you have Java installed ono your system, I recommend that you install this update as soon as you conveniently can.  You can obtain the new version, including the browser plug-in, from the Java download page.  Windows users can also use automatic updates to get the new release.


Google Releases Chrome 17·0·963·56

February 15, 2012

Google has released a new stable version, 17·0·963·56, of its Chrome browser, for Windows, Linux, Mac OS X, and Chrome Frame.   The new release contains fixes for 13 security vulnerabilities, six of which Google rates as High severity.     This release also includes a new version.,, of the bundled Adobe Flash Player.  More details on these changes are in the release announcement.

Windows and Mac users should get the new version via the built-in update mechanism.  Linux users should get the updated package from their distributions’ repositories, using their standard package maintenance tools.

Adobe Flash Player Security Updates

February 15, 2012

Adobe has released a new version,, of its Flash Player for Mac OS X, Windows, Linux, and Solaris.  The new version fixes seven identified security vulnerabilities, one of which (a cross-site scripting bug) is currently being exploited.  There is also a corresponding new version of FlashPlayer for Android.  Adobe reports that the following versions of the software are affected by these vulnerabilities:

  • Adobe Flash Player and earlier versions for Windows, Macintosh, Linux and Solaris operating systems
  • Adobe Flash Player and earlier versions for Android 4.x, and Adobe Flash Player and earlier versions for Android 3.x and 2.x

Further details are available in the Security Bulletin [APSB12-03].

The new version for Windows, Mac OS X, Linux, and Solaris can be downloaded here.  (Windows users should note that they may need two updates: one for Internet Explorer, and one for all other browsers.)   Android user can get the new version from the Android Marketplace.

Because Flash Player is very widely installed, across multiple platforms, it is an attractive target for the maliciously inclined.  I recommend that you update your system as soon as you conveniently can.


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