BPMN21 — Inconsistencies related to Default Sequence Flow

i) Chapter/Section 7.2.2. Page 34. Table 7.2. Row “Default flow”. It says:
“For Data-Based Exclusive Gateways or Inclusive Gateways, one type of flow is the Default condition flow …”
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ii) Chapter/Section 8.3.9. Page 90
According to Figure 8.24 a Sequence Flow can be the “default flow” of many Gateways simultaneously (see multiplicity [0..*] of roles exclusiveGateway, inclusiveGateway and complexGateway).

The same occurs in Figure 10.104 (p.297); Figure 10.107 (p. 299); Figure 10.109 (p.301); and Figure 10.114 (p.304).
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iii) Chapter/Section 8.3.13. Page 98. Figure 8.35.
Multiplicity of role “activity” (from “SequenceFlow” to “Activity”) is [1..1].

The same occurs in Figure 10.6 (p.155).
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iv) Chapter/Section 11.3.1. Page 330. It says:
“Default Sequence Flows: For Exclusive Gateways, Inclusive Gateways, and Choreography Activities that have Conditional Sequence Flows, one of the outgoing Sequence Flows MAY be a Default Sequence Flow. Because the other outgoing Sequence Flows will have appropriately visible of data as described above, the Participants would know if all the other conditions would be false, thus the Default Sequence Flow would be selected and the Choreography would move down that Sequence Flow.”
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v) Chapter/Section 11.4. Page 332. Figure 11.6.
“ChoreographyActivity” is not associated with “SequenceFlow” for optional default.

The same occurs in Figure 8.35, p. 98.
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COMMENTS:

In : “Default flows” are used by Complex Gateways and Activities too, but they are not mentioned. Furthermore, in BPMN 2 the name is “Exclusive Gateway” not “Data-Based Exclusive Gateway” (see p. 33)

In (ii): It is impossible for a Sequence Flow to be the “default flow” of more than one Gateway or Activity simultaneously, because a Sequence Flow has only one FlowNode as its sourceRef (Figure 8.35, p.98; see also Section 8.3.13).

In (iii): Multiplicity [1..1] of role “activity” (from “SequenceFlow” to “Activity”) means that every Sequence Flow is the default of exactly one Activity, which is not possible.

In (iv): Complex Gateways can have default in Orchestrations, but they are not mentioned for Choreographies (… For Exclusive Gateways, Inclusive Gateways, and Choreography Activities that have Conditional Sequence Flows …).

In (v): Choreography Activities can have default, but the corresponding associations between “ChoreographyActivity” and “SequenceFlow” in Figures 8.35 and 11.6 are not shown

SUGGESTIONS:

In : It says:
“For Data-Based Exclusive Gateways or Inclusive Gateways, one type of flow is the Default condition flow …”

It should say:
“For Exclusive, Inclusive or Complex Gateways, or Activities one type of flow is the Default condition flow …”

In (ii): Multiplicity of roles exclusiveGateway, inclusiveGateway and complexGateway in Figures 8.24, 10.104, 10.107, 10.109 and 10.114 should be changed from [0..*] to [0..1].
Furthermore, in Figures 8.24 and 10.104 a constrain

should be used in order to underline that a Sequence Flow cannot be a default flow of two or more Flow Nodes simultaneously (See OMG Unified Modeling LanguageTM (OMG UML), Infrastructure. formal/2009-02-04. Pages 41, 42, 43). This {XOR] must include the associations from “SequenceFlow” to “ExclusiveGateway”, “ EnclusiveGateway”, “ ComplexGateway”, “Activity” and “ ChoreographyActivity”.

In (iii): Multiplicity of role “activity” (from “SequenceFlow” to “Activity”) in Figures 8.35 and 10.6 should be changed from [1..1] to [0..1].

In (iv): If default are allowed in Choreographies for Complex Gateways, then “For Exclusive Gateways, Inclusive Gateways, and Choreography Activities that have Conditional Sequence Flows” should be replaced by “For Exclusive Gateways, Inclusive Gateways,, Complex Gateways, and Choreography Activities that have Conditional Sequence Flows”.

In (v): The corresponding model associations (between “ChoreographyActivity” and “SequenceFlow” : +activity [0..1] --> +default [0..1]) should be added to Figures 8.35 and 11.6.
Also, the corresponding row “default” should be added to Table 11.1 (p.332). (Similar to row “default” in Table 10.3, p. 156).