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Official Website of ASHRAE SSPC 135
This Website is dedicated to providing the latest information on BACnet - A Data Communication Protocol for Building Automation and Control Networks. Developed under the auspices of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), BACnet is an American national standard, a European standard, a national standard in more than 30 countries, and an ISO global standard. The protocol is supported and maintained by ASHRAE Standing Standard Project Committee 135 whose members have created and provided the content for this Website.

Here you will find the latest BACnet news, the status of SSPC 135 activities, a comprehensive bibliography of BACnet publications - many of which are available on-line - along with a wealth of other information. In keeping with ASHRAE's long-standing tradition and policy of non-commercialism, this site contains no advertising. However, BACnet's success depends on the implementation of BACnet in commercial products. Thus, we are pleased to offer links to the Websites of manufacturers who are supporting BACnet through their product offerings.

The SSPC welcomes your comments and suggestions concerning this site!

Latest News
  • Three New Addenda Published! (5/16) Atlanta, GA. The standard addenda listed below are now available for free download. These addenda make up protocol Revision 19 of the BACnet standard and are the last addenda to Standard 135-2012. They will be an integral part of the upcoming consolidated BACnet Standard 135-2016, soon to be published.

    • Addendum 135-2012am Extend BACnet/WS with RESTful web services for complex data types and subscriptions, extract the data model from Annex Q into a separate common model, rework of Annex Q to be an XML syntax for the common model, add a JSON syntax for the common model, deprecate Annex N SOAP services and add a migration guide, and change Clause 21 identifiers to use a consistent format.
    • Addendum 135-2012ba Add CSML based descriptions of BACnet devices, add Semantic Tags to all objects, extend Structured View object to contain semantic information on subordinates, and add data revisioning capabilities to CSML.
    • Addendum 135-2012bc Extend BIBBs for Primitive Value objects, add new BIBBs for event enrollment and subscription, amend B-AWS related BIBBs for revised event reporting, add life safety BIBBs and device profiles, add physical access control BIBBs and device profiles, and add an All-Domain Advanced Workstation (B-XAWS) device profile.
  • Five New Addenda Published! (3/16) Atlanta, GA. The standard addenda listed below are now available for free download here or on the ASHRAE website at: http://www.ashrae.org/standards-addenda.

    • Addendum 135-2012aj Add support for IPv6
    • Addendum 135-2012aq Elevator object types
    • Addendum 135-2012bf Advanced Network Configuration with the Network Port object
    • Addendum 135-2012bg Add engineering units, harmonize message text handling for all alarm services, ensure Alert Enrollment objects do not send notifications which require acknowledgment, allow selection of the Nth last day of the month in a BACnetWeekNDay, remove initiation of GetEnrollmentSummary from AE-AS-A, ensure UTC_Offset is configurable, clarify ReadRange service, clarify the effect of changing Buffer_Size, stop MS/TP nodes from sending POLL_FOR_MASTER frames to themselves, improve the Clause 12 preamble, fix the Notification_Class property of the Notification Class object.
    • Addendum 135-2012bh Correct Application State Machine Failover, increase Segmentation Window Size for MS/TP

  • SSPC 135 Concludes Productive Orlando Meeting (1/16) Zug, Switzerland. The BACnet committee assembled for another 4 1/2 days of working group and plenary meetings in Orlando, FL, in the course of the ASHRAE Winter Meeting and AHR Expo 2016. While the working groups were focusing on new work items and the resolution of public review comments, the plenary voted out comment responses to several major addenda. The resolution of comment responses resulted in editorial changes only. As a result, the following addenda are now on their way to being published:

    • Addendum 135-2012am defines new RESTful Web Services replacing the current Web Services that are based on SOAP. In addition, this addendum introduces the so-called BACnet Extended Data Model, also known as BACnet XD. These extensions allow for arbitrary structures, a uniform set of standardized metadata applicable to all data, a powerful mechanism for data relations, and a semantic information model.
    • Addendum 135-2012ba adds device descriptions based on BACnet XD using CSML as the language, and adds extended semantic information to objects and to relations in structures of objects.
    • Addendum 135-2012bc includes general BIBB updates for primitive value objects and the revised event reporting. It also includes new BIBBs and device profiles for both life safety and physical access control devices and applications. The new device profiles are added to the standard as new families, utilizing the device profile family concept introduced with Addendum 135-2012al, Protocol Revision 17.

    The above three addenda will make up Protocol Revision 19. The committee decided that they are to be published as addenda to the BACnet standard 135-2012. With that, they will flow into the projected new baseline 135-2016 of the BACnet standard, expected to be publicly available this spring.

    For BACnet, the RESTful Web Services Addendum 135-2012am is a major step towards support of modern IT technologies and integration with enterprise level applications, clouds, and modern user interfaces. Together with Addendum 135-2012ba, a higher level of semantic information can be provided that is consumable by machines, reducing costly manual engineering hours. On the completion of these two addenda, the committee specifically thanked and applauded former SSPC Chairman Dave Robin from Automated Logic who, as the major author of these addenda, spent an uncountable number of days and nights making possible this big achievement for the BACnet community.
  • SSPC 135 Wraps up Atlanta Meetings! (11/15) Atlanta, GA.The BACnet committee met in Atlanta, Georgia, November 2-6, once again graciously hosted by Georgia Tech.

    Highlights from the meeting include the following:

    • Addendum 135-2012aj, that adds support for IPv6, was recommended for publication.
    • Addendum 135-2012bf, that added extensions to the Network Port Object and adds clarifying text to Annex J, was recommended for publication.
    • Addendum 135-2012bg, that makes several miscellaneous changes throughout the standard, was recommended for publication.
    • The committee reviewed the proposal for adding audit logging and recommended it for publication public review as Addendum 135-2012bi.

    The SSPC thanks the committee volunteers for their attendance and ongoing hard work!

  • Three More Addenda Begin 60-day Public Review (10/15) Atlanta, GA. The following addenda have started their 60-day Publication Public Reviews which will run from October 20 until December 29, 2015:

    3rd Public Review of Addendum 135-2012am
    This addendum extends BACnet/WS with RESTful services for complex data types and subscriptions, extracts the data model from Annex Q into a separate common model, reworks Annex Q to be an XML syntax for the common model, adds a JSON syntax for the common model, deprecates Annex N SOAP services and adds a migration guide.

    4th Public Review of Addendum 135-2012ba
    This addendum adds CSML Descriptions into BACnet Devices, adds Semantic Tags to All Objects, extends Structured View Objects to Contain Semantic Information, changes Clause 21 identifiers to use a consistent format, and adds Data Revisioning Capabilities to CSML.

    2nd Public Review of Addendum 135-2012bc
    This addendum extends BIBBs for Primitive Value Objects; adds new BIBBs for Event Enrollment and Subscription; amends B-AWS related BIBBs for revised event reporting; and adds Life Safety BIBBs and Device Profiles, Access Control BIBBs and Device Profiles, and an All-Domain Advanced Workstation Profile.

    Click on the links above to see addenda content or visit www.ASHRAE.org to both get copies and submit comments.

  • Five Addenda Now Available for Public Review (8/15) Atlanta, GA. One of the main results of the April SSPC meeting in Ft. Lauderdale was the recommendation of five addenda for Publication Public Review (PPR).

    Recommended for a 5th PPR of Independent Substantive Changes was:
    Addendum 135-2012aj.

    The following four addenda are each undergoing their 1st PPR:
    Addendum 135-2012be;
    Addendum 135-2012bf;
    Addendum 135-2012bg; and
    Addendum 135-1-2013bh.

    Click on the links above to see addenda content and dates of the PPRs or visit www.ASHRAE.org to both get copies and submit comments.
  • SSPC Wraps up Atlanta Meetings! (7/15) Atlanta, GA.The BACnet committee met in Atlanta, Georgia at the end of June in conjunction with the ASHRAE Annual Meeting. Highlights from the meeting include the following:

    The various working groups met and continued making good progress on the respective work items. Highlights of the working group meetings include:

    • Continued work on test development across the board.
    • Continued work on Data Modeling and the proposed direction for IT interaction.
    • The Application Profiles Working Group continues to work with Project Haystack to ensure that the proposed tagging solutions are compatible.

    The plenary met for two days and recommended 3 addenda for public review: Addendum 135-2012bc was recommended for a 2nd Publication Public Review; Addendum 135-2012ba was recommended for a 4th Publication Public Review; and, Addendum 135-2012am was recommended for a 3rd Publication Public Review.

    This meeting marked Carl Neilsonís last meeting as the Chair of the SSPC and subsequent appointment of new Committee officers. Bernhard Isler will be assuming the role of Chair after having served as Secretary for 3 years and Vice-Chair for 3 years; Michael Osborne will be assuming the role of Vice-Chair having served as Secretary for 3 years, and, Coleman Brumley will be assuming the role of Secretary.

    The Committee thanks Carl for all of his hard work!

    Bernhard Isler becomes the 6th Chairman of the BACnet Committee since its inception in 1987.

    Pictured from left to right: Carl Neilson, Chair 2012-2015; Dave Robin, Chair 2008-2012; Bernhard Isler, Incoming Chair; Steve Bushby, Chair 2000-2004; and, Mike Newman, Chair 1987-2000. Absent is Bill Swan, Chair 2004-2008. Bill passed away in 2011.

  • Fourth Swan Award Presented to Coleman Brumley! (7/15) Atlanta, GA. During the June 27 plenary session of SSPC 135, David Fisher, President of PolarSoft Inc., announced the recipient of the fourth annual "Swan Award." Fisher reiterated the purpose of the award:

    "This award, which is presented yearly, honors the memory of our dear friend and colleague, Bill Swan, a.k.a. BACnet Bill, who passed away in 2011. We want to remember him always not only for his substantial dedication and contributions to BACnet, but also as a good and honest man, devoted to his family and faith. This award carries on Bill's example of even-handedness, rational and considerate discussion, and a focus on how to make the standard better for everyone. The award honors those individuals who through their actions demonstrate the qualities of integrity, selflessness, camaraderie and fierce dedication to the standard that we admired in Bill."

    Fisher explained that this year's selection was based on several criteria about the recipient:

    • Authored parts of the standard
    • Served as a Working Group convener
    • Was an implementer/product designer
    • Has provided education to others about BACnet
    • Has worked on behalf of BACnet with other groups, such as BACnet International
    • Has shared knowledge and experience with others through public forums such as LinkedIn and BACnet-L

    Fisher then presented the 2015 Swan Award to SSPC incoming secretary Coleman Brumley.

    "It is our intent to continue to sponsor these awards in the future," explained Fisher, also noting that he continues to encourage other organizations within the BACnet sphere who are interested in sharing sponsorship to contact him directly.

  • SSPC Wraps Up Meeting in Fort Lauderdale! (5/15) Ft. Lauderdale, FL. The BACnet Committee met at the end of April in Fort Lauderdale Florida. Here are some of the highlights from Chairman Carl Neilson.

    The IP Working Group spent time reviewing comments from the last public review of Addendum 135-2012aj (BACnet over IPv6). While most comments resulted in editorial changes, one comment resulted in a substantive change so the addendum has to go out for another public review. Given the size of the change, the review will be limited to just those areas substantively changed since the last public review.

    The IT Working Group continues on its path of developing a solution for BACnet over HTTP. The group is targeting the end of 2015 for an initial public review.

    The audit log solution being developed by the Network Security Working Group is nearing completion. The group is confident that a public review-ready addendum will be available at the ASHRAE Annual Meeting in Atlanta.

    Addendum 135-2012am, the rework of BACnet Web Services, was voted out by the committee for another public review and the committee is considering holding another virtual plugfest coincidental with the public review.

    The Applications Working Group made good progress at the meeting on its development of semantic tags. They are working with Project Haystack to ensure that the two approaches to semantic tagging are compatible and have some technical issues to work through to ensure this goal is reached.

    It was announced at the plenary session that Carl Neilson will be stepping down from the Chairís position after the Atlanta meeting at the end of June. Bernhard Isler, currently Vice Chair, will be taking over as Chair of SSPC 135 at that time.

    The BACnet Committee thanks Lutron for hosting the meeting at Lutronís Experience Center in Plantation, FL. The Committee also thanks Carl for his great work over the last 3 years and congratulates Bernhard on his new role as only the 6th Chairman of the BACnet Committee since it began in 1987. Good luck to both!

  • BACnet Positioned to Play Role in IoT! (4/15) Atlanta, GA. With the recent approval of Addendum 135-2012an, MS/TP is now capable of conveying "extended frames" with data lengths up to 2032 octets. Moreover, other protocols can now use MS/TP's EIA-485 medium access control (MAC) technology as their data link. One such application is the use of IPv6 over MS/TP which many believe will be a standard way for implementing the so-called "Internet of Things" (IoT). A significant step in this direction was taken on March 24 when ASHRAE assigned MS/TP Frame Type 34 to the Internet Engineering Task Force for using BACnet MS/TP as the standard MAC protocol for using the Internet Protocol over EIA-485 twisted-pair serial networks.

    Other standards development organizations that wish to use BACnet MS/TP as their MAC protocol for EIA-485 can also request assignment of a Frame Type from ASHRAE. The procedures for requesting a Frame Type can be found at https://www.ashrae.org/standards-research--technology/standards--guidelines/standards-activities (see the section on "BACnet Vendor ID Numbers").

  • BIG-EU Plugfest 2015 Announced! (4/15) Dortmund, Germany.The BACnet Interest Group - Europe (BIG-EU) has announced its 9th BACnet Interoperability Workshop, also known as a "Plugfest"! It will take place in Turin, Italy, May 20Ė22, 2015, and is open to developers and product managers. This year's host will be ESAC srl. Note that registration has been extended until Friday, April 24, so it is not too late to get in on the fun! For more information, please click here.
Coming Events

  • April 18-22, 2016, SSPC Interim Meeting, Ft. Lauderdale, FL
  • June 23-27, 2016, SSPC Meeting, St. Louis, MO
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