The WITS protocol is in continuous active development. New products should be developed against the most recent set of WITS Application Notes, claim compliance at the current WITS protocol version and use a current test specification.

Incremental changes to the major protocol version (e.g. 1.x->2.x) are assumed to involve significant changes to the software or system of a Field Device or Master Station. These may include significant new functionality, major changes to the protocol or large scale additions or changes to the protocol documentation. As a result, vendors wishing to claim compliance to an updated major specification change are recommended to complete full “Verified” status testing of their product.

A minor protocol version (e.g. x.1->x.2) is assumed to involve minimal or minor changes to the software or system of the Field Device or Master Station. These may involve small changes or additions to protocol functionality or clarifications to the protocol documentation. Therefore, once Verified status has been achieved at a given major protocol version, it is recommended that products only perform Self-Certification tests on further minor revisions of the protocol standard.

Example Case

A product undergoes updated certification as new versions of the protocol are issued:

1.WITS-DNP3 Version V1.2 is issued: Product undergoes the WITS Self Certification procedure. Product identified in the device catalogue as:

‘Self-certified at V1.2’

2.WITS-DNP3 Version V1.3 is issued: The same product is then verified against version V1.3. Product is identified in the device catalogue as:

‘Verified at V1.3, Self-certified to V1.2’

3.WITS-DNP3 Version V1.4 is issued: The same product does not implement this version of the protocol. Product is still identified in the device catalogue as:

‘Verified at V1.3, Self-certified to V1.2’

4.WITS-DNP3 Version V1.5 is issued: The same product undergoes the WITS Self certification procedure. Product is identified in the device catalogue as:

‘Verified at V1.3, Self-certified to V1.5’

5.WITS-DNP3 Version V2.0 is issued: This is a major release, however it is decided that the product will not implement this version of the protocol. Product is identified in the device catalogue as:

‘Verified at V1.3, Self-certified to V1.5’

6.WITS-DNP3 Version V2.1 is issued: This is a major release and requires mandatory testing as defined by the WITS Compliance Testing Manual in order to achieve ‘Verified at V2.1’ status. If a vendor decides not to Verify, once the product has completed the WITS Self certification procedure the device remains:

Verified at V1.3, Self-certified at V2.1’