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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
  • Fort Lauderdale Meeting Info Now Available! (3/17) Zug, Switzerland. SSPC Chairman Isler has announced the details of the committee meeting that will take place in Plantation, FL, a suburb of Fort Lauderdale, between April 24 and 27. Click here for the file.
  • BACnet User Group New England to meet on March 30, 2017. (3/17)  The next meeting of the BACnet User Group New England will be on Thursday, March 30, 2017 in Needham, Massachusetts.  The speakers will be Gabriel Kirby from LG and Mike Leathem from PTC.  All are welcome to attend, but preregistration is required.  Visit www.bacnetusergroupne.com for details.
  • Strides Made Towards Higher-Level Semantics! (1/17) Las Vegas, NV. During its winter meeting in Las Vegas, the BACnet committee made substantial progress towards the application of semantic information in BACnet and the creation of a general standard tag dictionary for building automation and associated building systems, useful in a broad range of applications and protocols, including BACnet.

    The semantic tagging concept for BACnet was voted out for an initial Publication Public Review as draft Addendum 135-2016bo. This tagging concept is foreseen to be a new BACnet Annex and defines how semantic tags from various dictionaries are applied in BACnet objects and the abstract data model (BACnet XD).

    For interoperable use of semantic tags, well-defined and robust standardized tag dictionaries are a fundamental prerequisite. The creation of a new ASHRAE standard, "Designation and Classification of Semantic Tags for Building Data", was proposed by the BACnet committee and approved by the ASHRAE Standards Committee. The new standard will provide a dictionary of tags for building automation and associated systems and protocols and is envisioned to ultimately become an ISO standard. Tags from this dictionary will be usable for tagging of building data in databases, protocols, BIM data, and other applications. For practical reasons, the draft of this new proposed ASHRAE standard 223P will be created and brought through the public review process by the BACnet committee. The formation of a dedicated project committee for this new standard and its future continuation and maintenance will be considered.

    Also related to higher-level semantics, the Elevator and Life Safety Working Groups held a joint Occupant Evacuation Operation (OEO) summit to discuss BACnet-based standardized application interfaces between fire alarm systems (FAS) and elevator systems (ES), for the purpose of OEO. This meeting was attended not only by BACnet people, but also by representatives from the fire and elevator domain. OEO is a relatively new concept, in particular for high rise buildings, enabling the use of elevators for the fast and safe evacuation of building occupants in the case of a fire. Aside from specific elevator and building construction requirements, OEO demands that FASs be able to provide detailed information about fire and evacuation states of floors to the ES, and that some state indications be available for transfer from the ES to the FAS. BACnet is considered a suitable protocol for conveying this information. As a result of this meeting, further work is planned by the Elevator and Life Safety Working Groups to create an initial draft of the application interface specification. This is a type of pioneer work, even for BACnet, above and beyond BACnet objects and semantic tags.

    Aside from work on pending addenda and proposals, Addendum 135-2016bi, Audit Reporting, was approved for a 3rd Publication Public Review of Independent Substantive Changes (ISC). Only a few substantive changes were needed after the second review and these will be open for review. A new draft Addendum 135-2016bp was also ready for review and will be approved off-meeting for its initial Publication Public Review. This new addendum will fix a number of small issues found by implementers of the BACnet RESTful web services defined in Annex W of BACnet.

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

  • Addendum-135-2016bj out for 1st APR! (12/16) Atlanta, GA. ASHRAE has announced the first Advisory Public Review of Addendum 135-2016bj from December 9, 2016 until February 7, 2017. This addendum extends the BACnet Architecture for Use of Internet Application Protocols; adds BACnet Virtual Router Link Half-Router; adds new Annex YY for the BACnet Virtual Router Link; adds new Annex ZZ, BACnet IT; adds and extends Object Types for BACnet/IT; adds and extends ASN.1 Types for BACnet/IT; introduces new Error Codes for BACnet/IT; and defines Interoperability Specification Extensions for BACnet/IT.

    To read a "white paper" written by the draft addendum's principal author and SSPC chairman Bernhard Isler, please click here.

    APRs are used to get informal public comments and guidance when a proposed addendum contains a significant amount of new material some of which may generate questions or controversy. They thus give the project committee an opportunity to resolve issues prior to publication review and thus help to expedite the standards development process.

    Please click on the link above to see the addendum's content or visit www.ASHRAE.org to both get a copy and submit comments.

  • BACnet-2016 Approved as ISO/FDIS 16484-5 (Ed 6)! (11/16) Geneva, Switzerland. The ISO Central Secretariat has announced that balloting has closed on the most recent edition of BACnet (BACnet-2016) as ISO/Final Draft International Standard 16484-5, 6th edition. The results were approved without a negative vote, 15-0-12. This means that BACnet implementers and users will be able to reference the international standard in their specifications and design documents, an important consideration in many parts of the world where such standards are required in public procurement and by some private concerns.
  • Fifth Swan Award Presented to Cliff Copass! (10/16) Atlanta, GA. During the October 25 plenary session of SSPC 135, David Fisher, President of PolarSoft Inc., announced the recipient of the fifth 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 (above right) then presented the 2016 Swan Award to longtime SSPC participant Cliff Copass (above left). "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.

  • 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.

  • 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.
Coming Events

  • April 24-27, 2017, SSPC Meeting, Plantation, FL
  • June 22-26, 2017, SSPC Meeting, Long Beach, CA
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