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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
  • Atlanta Meeting Details Here! (10/16) Zug, Switzerland. SSPC Chairman Bernhard Isler has published the details of the upcoming SSPC meeting in Atlanta. Click here for the information.
  • Big steps into IT environments and IoT! (7/16) St. Louis MO. The long anticipated BACnet/IT additions to the BACnet standard have been released for advisory public review (APR) as Addendum 135-2016bj. An advisory public review is a mechanism utilized by ASHRAE committees as a way to obtain market feedback and increased public scrutiny of the proposed material. BACnet/IT will enable BACnet to live in modern and managed IT infrastructures and applying IT security concepts in a way well known and accepted in such environments. In parallel to the public review, the committee is planning for an online plugfest to spark independent implementations for verification of the concepts. Details on this plugfest will be announced with the addendum going out for public review.

    Other items completed during the St. Louis meetings were: Addendum 135-2016be, Lighting BIBBs and Device Profiles, was released for 2nd publication public review; Addendum 135-2016bi, Audit Reporting, was also approved for its 2nd publication public review; and, the Data Modeling Working Group (DM-WG) discussed ideas for promoting BACnet/WS and how to use it with other protocols.

    The SSPC wishes to thank the volunteers for their time and effort on the BACnet standard.

  • St. Louis Meeting Details Announced! (6/16) Zug, Switzerland. SSPC Chairman Bernhard Isler has published the details of the upcoming meeting in St. Louis. Click here for the information.
  • 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 (now 2016bi).

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

Coming Events

  • October 24-27, 2016, SSPC Meeting, Atlanta, GA
  • January 26-30, 2017, SSPC Meeting, Las Vegas, NV
BACnet® is a registered trademark of American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). For more information see the notice. This web site is hosted by the BACnet Advocacy Group, you can find us Google+.