# Presentation: 834232

## A Systems Engineering ToolInteroperability “Plug-fest”

- Peter Denno
- National Institute of Standards and Technology

## Objectives of Presentation

- An overview of a *SE tools “Plug-Fest”* sponsored by NIST and DoD
- Motivation and Goals
- How it Works
- Rules of Participation
- Progress Toward the Goal to-date.

## Plug-fest Motivation & Goals

**Motivation:**
- The development of complex systems, and SoS, involves many disparate organizations, and is performed through their collaboration.
- These organization communicate through shared conceptualizations - Model-Based System Engineering (MBSE).
- Circumstances do not permit collaborating organizations to agree on a single SE tool. (And often not even on the same standard)
- Therefore tools must *interoperate.*
**Plug-fest Goal:**
- Provide facilities for tool developers to assess and improve the interoperability of their implementations

## Conformance and Interoperability

*Conformance testing* assesses whethersystem characteristics violate normative statements of a specification.
*Interoperability testing* assesses the ability to communicate information across tools,and thus the ability of parties to work jointly toward a goal.
- Conformance ought to lead to interoperability.
- But specifications may fall short

## Dimensions of interoperability assessment

- Test *Preservation of Information Content*
- Example: Certain information was present in the file read.Is it in the file written?
- Test *Comprehension of Content*
- Analogy: When we ran a CAD tool plug-fest, participants calculated the volume of a solid exchanged.
- Is there a similar test we can perform on SE data?
- “Executable SysML” ???
- Approach:
- What would any reasonable person infer from the data?
- Are there multiple tools that automate that inference?

## Schedule

- Gauge interest, get feedback (June/July '06)
- Define exchange scenarios (June/July '06)
- Develop initial exercise material (June/October '06)
- Start out easy. e.g. reqs or state chart scenarios
- You: Implement interfaces (June/Oct '06)
- ...if you haven't already
- We: Provide exercise material. (Nov '06)
- We: Hosts initial round of the plug-fest. (Nov '06)
- That is, get together (physically/virtually) to run exercises and discuss results.

## Approach

- Testing in rounds – every few months a new exercise
- Progressively more challenging problems
- Exercises consist of a general- and a technology-specific description of a model to create
- Each participant creates the model and generates an exchange file
- (SysML XMI 2.1, AP233 CD Part 28 XML, CADM XML)
- We provide tools to do a quality check prior to distribution to other participants
- Upload to the plug-fest shared repository. Notify others.
- Telecon to discuss results
- We collaborate on writing “recommended practices in file exchange”

## Ground Rules

- Anyone (with an implementation of any of the specs mentioned) can play.
- Cover your own expenses.
- We will only publish results “of a general nature.”
- Nothing attributable to specific applications / products.
- Detailed results are confidential.

## Progress Toward Goals

- Developed Exercises 1 and 2
- Developed tools (SysML / UML only, currently):
- Class Browser
- Structure checking “Validator”
- Model Diff

## Exercise 1

- http://syseng.nist.gov/se-interop/plugfest/test1/sysml

## Exercise 2

- http://syseng.nist.gov/se-interop/plugfest/test2/sysml

## Class Browser

## Validator

## Validator (2)

## Model Diff

- An “Interoperability Tool”
- Compare two models (e.g. two in-memory UML/SysML models) and report on the differences as 'edits' that will make one model identical with the other.
- Quick answer to the question “What did we do differently?”

## Miscellaneous Observations

- An interoperability hurdle at on the first line of an exchange file:
- <?xml version=”1.0” encoding=”windows-1252”?>
- Where in the Model we put things can differ:
- Model.ownedMember
- Model.packagedElement.packagedElement
- ...but perhaps this is OK
- UML 2.1 OCL is very buggy, SysML OCL is non-existent

## Things you can do now

- Try out the tools
- Get back to me with bug reports, etc.
- Create the model of Exercises 1,2
- Ask questions

## For More Information:http://syseng.nist.gov/se-interop/plugfest/or peter.denno@nist.gov