Different types of traces

The table below outlines the names, definition and definition relevant requirement to be used for the different types of trace that constitute a mapping statement. The names are inspired by the words from the SWIM Information Specification's requirements. This approach makes it clear which requirement is being satisfied by the trace.

Source and target of traces

The usual best start point when identifying a suitable AIRM concept depends on the type of information definition being traced. This can also give an indication on the type of trace to be used. The table below gives some general guidance on this.

Reading order of traces

General The standard requires multiple traces to be added to a mapping. The general reading order is:

1. "information concept" trace
2. "additionalnarrowing" traces (0..*)

or

1. "data concept" trace
2. "data type" trace (1)
3. "additionalnarrowing" traces (0..*)

All traces have an AND relationship.

The number of traces

The important thing when creating a mapping is to add sufficient traces to ensure that the semantics are understood. There is no need to add further traces.

If you find that too many traces are required to ensure that the semantics are understood, there may be a problem somewhere in fully understanding the meaning of a concept. In that case a change may be needed to the information definition and/or the AIRM.

Level of semantic correspondence

Advanced users may like to add extra detail concerning the level degree of semantic correspondence achieved. The skos standard calls this the "semantic relation" between concepts.

The requirements talk about mapping to the concept with "equivalent or wider meaning". The table below contains the old AIRM Rulebook names and the skos equivalentsoutlines the skos sematic relation term that can be used in order to make the level of semantic correspondence explicit. It also contain the equivalent terms that were used in SESAR.

Annotating traces

It is possible to add a further notes to the mapping (the container for one or more trace?). This comes in handy for example when e.g. tracing legacy interfaces that have data type constraints leading to loss of Information.

Recording traces in XSD

<xs:annotation>
  <xs:documentation>
    <semanticCorrespondence>
      <mapping note="loss <mapping>
        <note>loss of info because of legacy">legacy</note>
        <informationConceptTrace degreesemanticRelation="specialised">-AIRM unique identifier-</informationConceptTrace>
        <additionalTrace><narrowingTrace>-AIRM unique identifier-</additionalTrace>narrowingTrace>
      </mapping>
    </semanticCorrespondence>
  </xs:documentation>
</xs:annotation> 

<xs:annotation>
  <xs:documentation>
    <semanticCorrespondence>
      <mapping note="loss<mapping>
        <note>loss of info because of legacy">
        legacy</note>
		<trace type="informationConceptTrace" degreesemanticRelation="specialised">-AIRM unique identifier-</trace>
        <trace type="additionalTracenarrowingTrace">-AIRM unique identifier-</trace>
      </mapping>
    </semanticCorrespondence>
  </xs:documentation>
</xs:annotation> 

However it should be consistent with the information given at the AIRM homepage. Links to the according pages will also help.

Background

Existing qualifier names

Different artefacts have used different trace "qualifiers".

Example 1

1. "Data Traces", which, for the case of SWIM-INFO-017, refer to the Data Type constraints. They must be unique, and may already also contain the full definition (as the best matching AIRM concept with the correct data type constraint will be chosen), so they are logically first in line.
2. "Definition Traces" which point to the comprehensive or even normative definition (when available) or to the best matching wider AIRM concept (in both SWIM-INFO-016 and SWIM-INFO 017). They must be present and must be unique, so they are next in line (top of the line for SWIM-INFO-016 actually).
3. "Context Traces" that add qualifiers (i.e. implement SWIM-INFO-018). These are optional, and their order should not have semantic significance.

Example 2

The Donlon example at https://ext.eurocontrol.int/swim_confluence/display/SWIM/Donlon+TOBT+Setting+Service+Description#DonlonTOBTSettingServiceDescription-InformationDefinition is almost the same. It uses:

1. AIRM Semantic Trace
2. AIRM Definition Trace. This seems to be in line with what is mentioned above.
3. AIRM Context Trace. This appears to add the qualifiers as mentioned above.

Example 3

Looking at the ISRM (Information Service Reference Model) it has:

1. Main CLDM mapping. The mandatory and unique CLDM mapping indicating the AIRM element having the type of data as the OuA construct. E.g. a “time” for TSAT;
2. Context CLDM Mapping. One or more optional additional CLDM mappings helping achieving a more accurate semantic definition by giving more context to the main CLDM mapping. E.g. the “TARGET” planning status for TSAT;
3. IM Definition Mapping. An IM mapping allows referencing a unique IM element containing a normative definition (typically from ICAO) for the OUA construct. Can be optional or mandatory depending on contexts as explained in next chapters.

Example 4

EUROCAE ED-254.

The mappings to the AIRM have the following keywords:

1. SemanticTrace
2. DefinitionTrace
3. ContextTrace (which can be further defined as ContextTrace_1, ContextTrace_2, etc)

Keyword: DefinitionTrace.

Value: URN of an AIRM information or data concept

Usage Notes: This will normally point to a resource in the AIRM Information Model, i.e. an AIRM information concept. However, occasionally (e.g. when mapping the definition of certain containers), it may necessary to refer to the definition part of a (CLDM) data concept. In this case, the data type of the AIRM trace target is not part of the trace semantics.

Keyword: SemanticTrace

Value: URN of an AIRM data concept

Usage Notes: When there is no accompanying DefinitionTrace, it is understood that both SWIM-INFO-016 and SWIM-INFO-017 are implemented by this trace (see note on SWIM-INFO-017)

Keyword: ContextTrace / ContextTrace_n

Value: URN of an AIRM information or data concept

Usage Notes: The first form is the standard.  When more than one context traces is required on an element, the second form is used. The EUROCAE document does not formally associate business semantics with data entities, i.e. all data entities are implicitly traced to “OutOfScope: container”. The mappings of individual data fields are therefore self-contained, there is no “trace cascading”.

How many qualifiers

Can’t we survive on:

2 categories:

• “trace” (1 or more to either AIRM-CM or AIRM-LM; note that the URN shows whether CM or LM)
• “trace_qualifier”

In the schema trace and trace_qualifier could then be differentiated.

2 best practices:

• Order best practice: “widest first”
• Qualifier best practice: “Trace qualifier directly after qualified trace”

Adding notes to mappings

It is maybe worth noting here that sometimes you want to put a comment on a mapping, so I am allowing this as an extra annotation. This comes in handy for example when tracing legacy interfaces that have data type constraints leading to loss of Information.

Perhaps we need to look at what "aspects" of the AIRM model are mappable to first -  and also possible the level of alignment (eg exact, broader, etc aka SKOS-like).

The 'Definition:Adapted' AIRM::TaggedValue shall be completed in order to indicate the level of semantic correspondence with the source definition. The list of values is:

• ExactCopy: Definition of source and target are exact copy of each other.

• SyntacticallyEqual: Syntax corrections (grammar, spelling)

• Rewritten: The definition has been rewritten for improved quality. The meaning is the same, i.e. the definition still describes exactly the same entity as the target definition.

• Specialised: Source definition is a special case of the target definition.

• Generalised: Source definition is a generalised case of the target definition.

AIRM_Rule 116

A data or information construct is considered to be in semantic correspondence with the AIRM if one of the following conditions holds: