Ballot 10 - HART Specifications - Member Comments Requested
Notice and Call for Disclosure of Conflicting IPR
Extended Deadline: November 7, 2022
All FieldComm Group members, who haven't reviewed and submitted comments, are encouraged to do so now. The deadline has been extended to November 7. We appreciate your time and support!
This ballot proposes enhancements to three HART Technical Specifications:
  • Network Management (TS20085 v4.0)
  • Command Summary (TS20099 v11.0)
  • Common Practice Command (TS20151 v13.0)
Upon membership approval, these specifications will constitute HART 7.09. The proposed specifications consists of 6 major improvements:
  • SafeHART (Network Management)
  • Digital Write Protect (Common Practice)
  • Simpler Generic Host (Command Summary)
  • DiffServ (Common Practice)
  • mDNS (Network Management)
  • DNS-SD (Network Management)
In addition, per our standard practice, editorial improvements, clarifications and corrections were made as part of the general review of the specifications. The development of each enhancement is summarized in the following section.
  • Network Management Specification (HCF_SPEC-085, FCG PS20085, Revision 4.0) proposed three major improvements: SafeHART (a safety communication layer for the Protocol); support for multicast Domain Name Services (mDNS); and DNS- Service Discovery (DNS-SD).

    SafeHART provides additional message integrity checks that are calculated independently of the underlying transport (HART 4-20mA, WirelessHART, HART-IP). In addition, specific requirements and procedures complying with IEC 61508 are included for both for client applications and field devices. Net effect is SafeHART exceeds the SIL 3 communication budget's "Probability of Failure / Hour" (PFH) of 10-9/h.

    In addition, HART-IP is enhanced to support mDNS and DNS-SD. These further simplify deployment of HART-IP devices and networks. mDNS and DNS-SD enable zero configuration ("ZeroConf") deployment in most networks (with or without DNS and DHCP servers).

    DNS-SD enables directories of HART-IP network devices to be constructed and presented to the user. These listings allow the HOSTNAME, Unique ID, Manufacturer, Device Type, instrument type, and more to be previewed without physically opening a session to the device.

  • Command Summary Specification (HCF_SPEC-099, FCG PS20099, Revision 11.0) proposed functional simplifications and rationalizations of the Host Conformance Classes (in general) and the requirements for "Generic Hosts" (in particular). Many esoteric commands were delisted from these requirements and a few additional commands are specified to support HART-IP and Discrete Devices. The net result is a simplification to the requirements.
  • Common Practice Command Specification (HCF_SPEC-151, FCG PS20151, Revision 13.0) proposes six additional commands to support Digital Write Protect and DiffServ.

    DiffServ is used to enhance Quality of Service (QoS) in HART-IP networks. Since 2000, the Differentiated Services (DiffServ) standard has allowed IP communication traffic to be classified and QoS for that traffic to be assured.

    Digital Write Protect controls the Write Protect mode remotely via Digital Safety Locks. Placing Digital Write Protect in Read-Only mode has the same effect and installing the hardware write protect jumper. Conceptually, Digital Write Protect operates in a fashion similar to the widely used Lockout-Tagout safety practice.
In addition, per our standard practice, editorial improvements, clarifications and corrections were made as part of the general review of the specifications.
In addition, this announcement also serves as the Official Notice and Call for Disclosure of “any Private Intellectual Property Rights, existing under the law of any nation, owned by either a member or non-member that would conflict, legally bar or adversely affect application or implementation of the proposed Specification in any commercial products.”

To report the existence of any IPR that may conflict with the proposed specification, please go to our Support Portal and submit a ticket (choose "IPR Notification" from the drop down menu) within a 90-day period.
While only your company's voting contact can submit a vote on this ballot, ALL FieldComm Group members are welcome to review and submit their comments. To submit your comments, please follow these simple steps:
  1. Review the proposed specifications. Download the specifications from:

    You will need to create an account on FieldComm Group Workspace if you don't have one, to access the specifications.
  2. Submit comments:
    While the Primary Voter is responsible for submitting an official ballot, anyone in your company can submit comments for the proposed technical specifications:

    Once you are on the page, please click on the arrow next to the DOWNLOAD button and choose ADD A COMMENT.

  3. Submit your comments by November 7, 2022!
Have questions?
Please contact us at
Review and Submit Comments