May 2008

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Beyond Open Systems

  Anno Scholton


Anno Scholten
Novus Edge

Open systems in building automation have come a long way.  When I first became involved in building control systems many, many years ago, open protocol systems were well established.  Control components such as thermostats, damper actuators, valve actuators, humidistats, etc were not only interoperable but fully interchangeable from one manufacturer to another.  Of course, the common protocol was a 3 – 13 psi pneumatic signal (20 – 90 kPa for us international types), but it was well understood by everyone; the chiller mechanic, the controls engineer, the building manager and even the building tenant.  We probably all remember adjusting the thermostat and hearing the ‘pssst’ as we twiddled it around the set point, immediately telling us it was working correctly.  To accomplish the same thing today, I need a laptop with an 802.11 connection to the BAS network router, and have to initiate a TCP/IP session with the temperature sensor either with an HTTP Browser, BACnet/IP or LON protocol to adjust the current set point.  The system would then send an email to my PDA to confirm that some one had adjusted the set point in room T403.  Of course, my iPhone has now removed the need for my laptop.

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Open systems are truly successful.  Market demand is at an all time high.  Most control system manufacturers can now provide BACnet, LON and Tridium web solutions, and most are working on WS/XML oBIX solutions.  Open systems’ success has been due to the hard work and dedication of many people in this industry.  I’m sure we all remember the long hours put in by the developer community at events like BACnet Plug-Fests or LonMark Interoperability meetings to show that the technology really worked.  Customers, sales and marketing people presented case study after case study of successful open system implementations at BuilConn, RealComm and other conferences.  System integrators and the engineering community invested significantly in training on open system technologies.  And finally, the hard work that Standards bodies such as LonMark, BTL and OASIS have provided guarantees that we don’t wander from the path.  As a community, we should be proud of our open systems accomplishments.

The question now becomes, where do we go next?  I believe we can take one more page from the Telecommunication/IT, industry’s history book to help answer this.  Just like in my early years, the telecommunication industry had an interoperable and very interchangeable open standard for telephone exchanges.  The common protocol was English delivered by many operators sitting in large rooms with large patch panels.  With the advent of electronics, manufacturers developed their own proprietary telephone exchange technologies and protocols.  In 1992, the industry developed CSTA (Computer Supported Telecommunications Applications) as a standard abstraction layer for telecommunications applications that was independent of the underlying protocols.  It became an OSI standard in July 2000 and is still maintained by ECMA today.  Many large telecommunications companies built large proprietary and expensive PBX solutions on top of the CSTA open standard. 

Then in 1999, Mark Spencer of Digium, Inc created Asterisk, an open source implementation of a PBX.  By supporting a mix of traditional and VoIP telephony services, Asterisk allows developers to build new telephone systems, or gradually migrate existing systems to new technologies. Some sites are using Asterisk servers to replace proprietary PBXs; others to provide additional features (such as voice mail or phone menus) and others to cut costs by carrying long-distance calls over the Internet.  Since Spencer released Asterisk to the world in 1999 as an open source telephone operating system, it has been downloaded 500,000 times, and is currently downloaded 1,000 times per day. Some 350 open source contributors have taken it from a basic voice system to one with clear calling and more than 100 features.  Asterisk is now released under GPL (GNU General Public License).  The benefits of open source initiatives are well understood.  It is a very pragmatic way of evolving software in a rapidly changing environment. It harnesses the collective wisdom, experiences, expertise and requirements of its most demanding users to ensure that their needs are rapidly met.

Clearly open source is in our future.  However, just as open source telephone handsets are unrealistic, I don’t expect open source thermostats and controllers.  What I do see is an open source development platform that can provide the infrastructure for powerful open solutions to our open systems.  Our industry has many very smart, very experienced people who could release the power of open systems with an open source platform.  Today, our ability to develop applications on top of BAS systems is limited by the small number of gateway technologies available and no common development platform.  Open source is a natural next step.

Open source does have its obstacles.  To be truly successful, many people need to be involved.  Asterisk now has more than 350 contributors and Linux has thousands.  I feel that globally there are more than 100 individual contributors in our industry who could get started with an open source initiative today.  Software patent conflicts and security concerns have the potential to restrict innovation, but open source technologies have begun to address these.  More significantly, the challenge for open source, as with any emerging technology force, is to continue to be innovative while delivering high-quality products.  Compliance testing and certification must be a critical charter of any open source project.  Similarly, training and support must be available for both the platform and application development.  Fortunately, the Open Source Initiative, amongst others, has addressed many of these issues.

contemporary I expect there will be many who will dismiss open source as low quality developments not suitable for commercial deployment in mission critical facility systems.  I also think that some will feel threatened by the disruptive nature of open source developments and believe that their current technologies provide better capabilities than any first generation open source solutions.  This is also what Avaya, Northern Telecom and others thought when Digium released their first generation PBX based on open source Asterisk. 

Imagine if we had an open source application development platform today.  Think about the new applications that our clever people could build tomorrow to extract new value from the open systems being installed right now, and the plethora of legacy systems already installed.  Think how quickly we could develop enterprise connectivity solutions, or energy data analysis applications, or the next generation web user interfaces, or a SOA solution.  And you probably know someone right now who could do it.  More importantly, I believe we have several companies now who are ideally positioned to lead the charge on an open source initiative.  The leaders in the industry who had the vision of and established open systems realize that their significant value is in not in the underlying infrastructure but rather the applications and services they’ve created.  Something that Avaya and Northern Telecom realized when they finally embraced open source.  Open source is a unique opportunity for one of these leaders to continue their vision and drive this initiative.  Utilizing the same resources that our community used to deliver open systems, open source will release the ultimate potential of all systems.

As we head into a recession with more product development budget crunches, I think we'll see the next wave of open source adoption in all industries.  If it's good enough for telcos, banks, and the largest web sites, maybe it's good enough for us.  I believe the best place to start a discussion on how we can leverage open source for open systems is at ConnectivityWeek in Santa Clara.  I will be chairing an open invitation round table on Monday evening, May 19th at ConnectivityWeek.  If you feel that you would like to be part of  “Open Source for Open Systems” at this meeting please send me an email.

ConnectivityWeek will also have an excellent track on Tuesday, May 20th on Enterprise Interoperability that will have several thought leaders on open source.

About the Author

Anno Scholten has more than 25 years experience in the controls, security and building automation industries. Before joining NovusEdge, Mr. Scholten was CTO for Plexus Technology, Inc. where he was responsible for market development of Plexus’ web based solution for building automation systems. Prior to that, he was VP of Engineering for CSI Control Systems (now TAC), a worldwide building automation system provider. As an innovator and thought leader in the industry, Mr. Scholten has also served on many key industry standards committees and holds a US patent on a VAV Controller Using Fuzzy Logic.


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