Host Testing Provides the Basis for Interoperability
Within the Fieldbus Foundation's automation infrastructure,
interoperability is possible because devices and software must all
conform to the same standard and they are tested and registered to that
standard. Products bearing the FOUNDATION
Product Registration symbol have undergone a series of common tests
administered by the Fieldbus Foundation. End users can select the best
device for a specific measurement or control task, regardless of the
manufacturer.
Host registration provides an extra measure of confidence that fieldbus systems incorporate the robust functionality of FOUNDATION
technology and are able to function as part of an open, interoperable
control system. The host has been of particular concern in the past
because it is the key element at the system level and can determine the
success or failure of a fieldbus project. If your host is not
registered and tested, you are taking some unnecessary chances and have
no way of knowing if your host will work with a wide range of H1 and HSE
devices from different suppliers.
History of Host Testing: From HIST to Host Profile Registration
The Fieldbus Foundation has been doing host testing since its earliest
days. Over the years, this process has evolved considerably. The
Fieldbus Foundation's previous Host Interoperability Support Test (HIST)
provided a host test protocol with no provision for formal product
registration. With HIST, all the work was done by the host vendor. It
soon became clear, however, that testing and registration of hosts was
necessary. That’s when the Foundation introduced our Host Profile
Registration Process.
Under the new Host Profile Registration Process, the Foundation conducts
functional testing with a test device and specialized test Device
Descriptions (DDs) and Capabilities Files (CFs). Registered devices from
different vendors are also used during testing. The host profile under
test must support a clear set of required features. A host will
conform to some, or perhaps all, features as defined by the host feature
checklist. However, because hosts can have various definitions, not
all features may be applicable to a host implementation. Therefore, it
is not expected that every host should support each feature.
Each feature contains a set of test procedures that are to be run
against the host or the fieldbus system using the host. In order for a
host to claim conformance to the feature, the host must be able to pass
the test procedures defined by the feature. The features themselves are
generic; therefore, manufactures will derive test cases, or actual
implementation steps necessary to meet the requirements of the test
procedure. Fieldbus hosts successfully completing the test requirements
are authorized to bear the official FOUNDATION product registration symbol.
To view a complete list of registered Foundation fieldbus hosts, visit the registered host page.
Host Profiles and Classes
A host profile defines a minimum set of FOUNDATION-specific
features that must be implemented by a host to achieve compliance to a
specific host class. A host may incorporate one or more hardware and
software components as defined by the host manufacturer. Currently, the
Fieldbus Foundation defines four profile classes. These include:
- Class 61 – Integrated Host: Primary, on-process host that manages the communication and application configuration of all devices on a network
- Class 62 – Visitor Host: Temporary, on-process host with limited access to device parameterization
- Class 63 – Bench Host: Primary, off-process host for configuration and setup of a non-commissioned device
- Class 64 – Bench Host: Primary, off-process host with limited access to device parameterization of an off-line, commissioned device
- Class 71 - SIF Integrated Host: Primary on-process host for Safety Instrumented Functions
Each of these host classes has its own set of characteristics, primary
end users, and use cases. For detailed information about each of these, please click here.
It is important to understand what host testing and registration means to the end user. We have created a white paper specifically to help better understand the process.
Understanding Host Profile Testing and Registration
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