SysML FAQ: What is new in the OMG SysML v. 1.6 minor revision?

OMG SysML v. 1.6 Minor Revision Change Summary:

1. Block-typed Properties without Associations: Properties typed by Blocks must no longer be defined as an end of an Association. Consequently, you can now create Part Properties in an Internal Block Diagram without modeling a Composition Association relationship in a Block Definition Diagram (BDD).
2. Interface Block Realization and Conjugated Ports: Interface Blocks can be Specialized (inverse of Generalized) by Blocks so that they Realize (i.e., Implement; cf. Inherit) the Interface Block’s Flow Properties. In addition, the Realized Interface Block Flow Properties can subsequently be Conjugated.
3. Property-Specific Types: The syntax and semantics of Property-Specific Types are clarified.
4. Improved Well-Formedness Rules: A substantial amount of precise Natural Language semantics has been replaced by OCL WFRs.
5. Naming and Compartment Labeling Conventions: Various tweaks were made to Stereotype names and Block compartment labels to improve consistency and readability. Binding Connector keyword notation supports both “«equal»” and the symbol “=“.

Unsubstantiated Claims:
N/A

Critical Commentary:

• Change# 1 breaks the Definition/Usage dichotomy pattern of BDDs/IBDs, which is based on the Definition/Usage pattern of UML2 Class/Composite Structure diagrams, for no good reason. This will be impractical for SysML tool vendors to implement, and (if it has merit) should be deferred to the UML 2 major revision.
• Change# 2 conflates Generalization/Inheritance with Realization semantics and indicates that the current Revision Task Force (RTF) is confused about the syntax and semantics of SysML’s parent language (UML 2.x). This is another non-minor change that should be outside the scope of a minor revision.
• Change# 3 is an academic tweak to an impractical language feature.

Download:
You can download the OMG SysML v. 1.6 specification, as well as specifications for previous versions, from the SysML Specifications page.