Timing or change management information needs to be able to be associated with anything as anything can change over time. This includes for example with Attributes (and any Properties). In addition, how to best handle changes and change information over time needs to be reviewed throughout SACM.

The version and change management related information ­ although often kept in a CM system ­ needs to be exchangeable along with an assurance case. At least one exchange standard for CM information exists, TECHAMERICA EIA-836B: Configuration Management Data Exchange and Interoperability, publication date: Mar 1, 2010. It is reportedly both ANSI and DoD approved. (http://engineers.ihs.com/document/abstract/BMVKACAAAAAAAAAA) One option is for this to be appropriately included by reference.

Versioning should be available for everything. Identification and “HasVersion” attribute should be associated with a near root element, or this availability should be achieved in some other fashion. The standard should not restrict its availability and smallness of possible granularity of elements it may be applied to.

This level of fine grained versioning is outside the scope of SACM.

Versioning has been maintained as an attribute for the Artefact class, because in SACM’s management of evidence we are responsible for ensuring the complete and correct management of the artefact inventory. However, versioning of all of the other model elements lies outside the scope of the exchange model.

Comment – there must be other fine-grained model management / versioning standards) Versioning information could be added to every model element (if required) using TaggedValue (which could use a community consensus vocabulary established using the Terminology package). However, because there are many ways to maintain version information, we decided to not standardize this.

SBVR should be available in SACM for use wherever this would make sense. This includes in (ARM) claims and ReasoningElements and in SAEM many assertions particularly claims and possible rationales. Wherever narrative or prose, or mathematical expressions are allowed, why not also allow SBVR (and some places graphics or even other media also) unless strong reasons exist for doing otherwise?

Addressed by harmonization to create SACM 2.0.

The underlying intent of this issue has been fundamental in shaping the redefinition of SACM 2.0. The authors agreed with the need to provide a means of establishing structured expressions and vocabulary for both the Artefact and Argumentation parts of SACM 2.0. These structured expressions can be standardized for communities of practice through common terminology packages. We did not use SBVR and the fact model approach of SBVR as the means of doing this because it was considered too heavyweight for our purposes.

The following aspects need to be accommodated:
Owning, creating, and approving can be done concurrently by multiple entities and different (sets of) entities over time.

Ownership can be divided unequally among owners and fractions could need to be recorded.

Ownership can have aspects, for example IP rights versus physical object ­ I own the book, but not its copyright.

Addressed by harmonization to create SACM 2.0.

SACM 2 allows explicit representation of Participants in the Artefact model. This allows the representation of stakeholders. It also now provides a very flexible means of documenting multiple relationships (using ParticipantRoleRelationship) between Artefacts and Participants.

With integration EvidenceProperty inherit from Property as should all properties - directly or indirectly.

Removed multiple inheritence and different definition path.

The only occurrence of Properties within SACM 2.0 is with the class ArtefactProperty, which inherits from ArtefactAsset. There are no longer any other (inconsistent) definitions of properties with different inheritance.

From the viewpoint of compatibility with ISO/IEC 15026, the most important issue is that SACM contain an "Uncertainty" characteristic or attribute, a key aspect of 15026-2, in order to facilitate use of SACM with ISO/IEC 15026 conformant assurance cases. These would be useful throughout SACM as attributes of assertions or claims (not relations).

Current usage means a need exists for several data type options ­ not necessarily mutually exclusive.

Data Types
• Probability true: 0-1.00
• Type I error: 0-1.00
• Type 2 error: 0-1.00
• Enumeration: None, low, medium, large, unknown
• Standard deviation: real number
One might also want to include a data type with customizable meaning (values: 1-100) that would parallel the data type for “Strength” in present draft if this is retained.

This attribute element is associated with claims (assertions) and not with relations. Current SAEM draft defines characteristics ­ such as “Strength,” and “Confidence” ­ of evidence relations between an EvidenceItem (e.g. exhibit) and a DominAssertion. These relate to uncertainty but are associated with a relation and not with a DomainAssertion (claim). Note that the draft of SAEM states these are one-to-one relations unlike the many-to-one inferential relations in ARM.

Addressed by harmonization to create SACM 2.0.

In redefining SACM 2 it was recognized that there was no established approach (accepted by even a small group of industry) as to how to represent confidence and uncertainty on SACM artefact and argumentation elements. Consequently, SACM 2 deliberately pulled back from standardising in these areas. Confidence information could be added to any model element (if required) using TaggedValue (which could use a community consensus vocabulary established using the Terminology package). In addition, SACM 2 recognises that substantiative assertions about artefacts / evidence should be documented as Claims. It also recognizes the potential (which may be particularly relevant when discussing confidence) to attach metaclaims to any Assertion (see metaClaim association on Assertion).

2. What is needed to be known by tool or human is information required to establish the meaning of its content (interpret it) for this the notation/means used to express contents needs to be identified. An associated property could do this ­ and with more power/flexibility as any notation could be identified. Among other things, one should not presume that multiple tool vendors would never chose to support a (mathematically) formal notation other than SBVR. The use of different element types to identify nature of contents as “informal” or “structured” would be overkill. Rather, rename/combine “Consistency,” “ IsExpressed InLanguage”or other element to NotationUsed and provide appropriate attributes.

This level of prescription of description is no longer included in SACM 2.0.

This level of prescription of description in the Artefact model (i.e. referring to the form of expression of artefact contents) is no longer included in SACM 2.0. However, a community could standardize on an expected set of ArtefactProperties, description of these properties and vocabulary using a common Terminology Package.

Timing or change management information needs to be able to be associated with anything as anything can change over time. This includes for example with Attributes (and any Properties). In addition, how to best handle changes and change information over time needs to be reviewed throughout SACM.

The version and change management related information ­ although often kept in a CM system ­ needs to be exchangeable along with an assurance case. At least one exchange standard for CM information exists, TECHAMERICA EIA-836B: Configuration Management Data Exchange and Interoperability, publication date: Mar 1, 2010. It is reportedly both ANSI and DoD approved. (http://engineers.ihs.com/document/abstract/BMVKACAAAAAAAAAA) One option is for this to be appropriately included by reference.

Versioning should be available for everything. Identification and “HasVersion” attribute should be associated with a near root element, or this availability should be achieved in some other fashion. The standard should not restrict its availability and smallness of possible granularity of elements it may be applied to.

Deferred as still valid for SACM

This is still felt to be valid issue, and it remains a difference between the evidence and argument portions of SACM. However, it still remains unclear how best to address this fine-grained change management and versioning issue for individual model elements (e.g. individual claims).

As everything is disputable (that is, can be challenged) and issues of many natures can arise, a general “Issue” facility is required. This should also span all of SACM.

Currently, “EvidenceObservation” is used in the sense of “comment” or “issue”. Its name could be changed and its availability be made more general. Possibly it should include a sub-element with a more general name for issues that do not fit into current sub-element categories (or possibly not yet categorized).

While probably not belonging in the core compliance point, facilities for issue resolution need to be likewise generally applicable.

Change not considered necessary

Felt not necessary to have specific Issue element as general commenting and issue tagging can easily be done with TaggedValue which already exists.

From the viewpoint of compatibility with ISO/IEC 15026, the most important issue is that SACM contain an "Uncertainty" characteristic or attribute, a key aspect of 15026-2, in order to facilitate use of SACM with ISO/IEC 15026 conformant assurance cases. These would be useful throughout SACM as attributes of assertions or claims (not relations).

Current usage means a need exists for several data type options ­ not necessarily mutually exclusive.

Data Types
• Probability true: 0-1.00
• Type I error: 0-1.00
• Type 2 error: 0-1.00
• Enumeration: None, low, medium, large, unknown
• Standard deviation: real number
One might also want to include a data type with customizable meaning (values: 1-100) that would parallel the data type for “Strength” in present draft if this is retained.

This attribute element is associated with claims (assertions) and not with relations. Current SAEM draft defines characteristics ­ such as “Strength,” and “Confidence” ­ of evidence relations between an EvidenceItem (e.g. exhibit) and a DominAssertion. These relate to uncertainty but are associated with a relation and not with a DomainAssertion (claim). Note that the draft of SAEM states these are one-to-one relations unlike the many-to-one inferential relations in ARM.

Deferred as still valid for SACM

Whilst still a gap between what is discussed in ISO 15026 and what is supported in SACM, it was recognized that there still is no common established state of the practice for recording confidence and uncertainty values on assurance case argument elements. It may be that a probability value would allow for the most commonality amongst current approaches. Guidance would be required on how to map to a probability value under different confidence determination regimes as listed above. There was still some disagreement about whether the current approach to modeling confidence in the evidence portion of SACM is fit for purpose. However for backward compatibility now changes have been made to this.

SBVR should be available in SACM for use wherever this would make sense. This includes in (ARM) claims and ReasoningElements and in SAEM many assertions particularly claims and possible rationales. Wherever narrative or prose, or mathematical expressions are allowed, why not also allow SBVR (and some places graphics or even other media also) unless strong reasons exist for doing otherwise?

Deferred as still valid for SACM

The RTF still recognize the important of supporting structured expressions (as could be done with SBVR). However, it has not been possible to harmonise the evidence part’s use of SBVR with an approach to use in the argument part.

The following aspects need to be accommodated:
Owning, creating, and approving can be done concurrently by multiple entities and different (sets of) entities over time.

Ownership can be divided unequally among owners and fractions could need to be recorded.

Ownership can have aspects, for example IP rights versus physical object ­ I own the book, but not its copyright.

Deferred as still valid for SACM

This can be handled at present using the adhoc mechanism of TaggedValue. However, it is recognized that a more systematic solution is desirable. It is recognized that multiple stakeholders may have various roles with respect to assurance case elements (e.g. proposer, reviewer, endorsement). In addition, it could be useful to link these roles to a lifecycle model (similar to that proposed for Evidence in Section 7.7). This issue should be taken forward with the resolution of the change management and version control issue (16281).

The term “Exhibit” should be replaced with Artifact” because some Exhibits/Artifacts are not evidentiary but are descriptive or, for example, provide definitions in other words they have other roles than exhibits constituting evidence.

Change not considered necessary

Discussed at Boston 2014 June meeting and decided that this change is not necessary and that the issue should be closed.

2. What is needed to be known by tool or human is information required to establish the meaning of its content (interpret it) for this the notation/means used to express contents needs to be identified. An associated property could do this ­ and with more power/flexibility as any notation could be identified. Among other things, one should not presume that multiple tool vendors would never chose to support a (mathematically) formal notation other than SBVR. The use of different element types to identify nature of contents as “informal” or “structured” would be overkill. Rather, rename/combine “Consistency,” “ IsExpressed InLanguage”or other element to NotationUsed and provide appropriate attributes.

Deferred as still valid for SACM

The extension and unification of language and vocabulary support in revision to SACM would require a substantial change that would significantly negatively impact backwards compatibility that is beyond what can be done in SACM 1.1.

With integration EvidenceProperty inherit from Property as should all properties - directly or indirectly.

Deferred as still valid for SACM

To address this in revision to SACM would require a substantial change that would significantly negatively impact backwards compatibility that is beyond what can be done in SACM 1.1.