Ideal Model Management

1.     The future (ideal?) Model Management system (where we want to be…) - Mark Sampson, Lonnie VanZandt

The ultimate vision of a cross-domain model management system is to provide the framework  within which all models can contribute the perspective on a design choice.  Cost, reliability, performance, behavior, safety, and many others each provide their own view.  Providing a framework for balancing those views means not only capturing and managing the models and their interfaces, but also the information exchange among the many different models to enable global product optimization.  INCOSE’s MBSE vision describes how a framework could be used to handle complex tradeoffs to communicate that vision:

The scenario describes a ‘simple’ change around vehicle braking distance with models reporting back a variety of impacts at fine-grained level (inside models) presented in an abstract way for human consumption.   In this case the change in the braking distance effects regulatory compliance, thermal management, ergonomic parameters, hydraulics, automatic cruise control, Mean-Time-Between-Failure predictions, and electrical subsystem design.  Since not all impacts are direct (some are secondary, tertiary, or farther removed) the models supports drilling/navigating into model predictions to discover the underlying relationships and impacts of the model interactions.  

Ultimately it may be possible to have models self-organize and self-optimize. More achievable in the near term would be capability that enables users to quickly see the impacts of decisions by interacting with models and getting real-time feedback on how product behavior is changing during the decision making process.  

What steps need to be taken to accomplish this vision:

• Managed models
• Agreed interfaces
• …
• …

Define requirement/specification for “ideal model management system”

a.       Requirement for future state MM system

                                                               i.      Define Use Cases and Requirements for effective Model Management

                                                             ii.      MM as part of broader, cross domain, systems artifacts management (e.g. relations to requirement management, quality/test management etc. )

1. Identify emerging approaches (from section #4 and beyond) to MM that support the use cases and requirements and address the technology and methodology gaps  

Ideal Capabilities

The following unordered statements express the capabilities the authors propose a hypothetical, exemplary system for the management of models will offer.

• Identifies users and appropriately challenges users for access authority
• Distinguishes curated information from capricious information
• Informs the reader of the provenance of curated information
• Stores Measures of Confidence for the existence of information
• Notifies a subscriber of changes to subscribed information
• Notifies a user of the foci of peer users
• Provides confidentiality through Role-based Access Controls
• Automatically preserves historical snapshots
• Offers access to historical snapshots of information repositories
• Illustrates differences between historical snapshots
• Composes model modules over levels of abstraction, disciplines, and access rights

Indicative Use Cases

The following Use Cases indicate the need for the aforementioned ideal capabilities of model management.

• Use Case: A stakeholder of a model who is not the editor of the entire set of information within the model needs curated information within the model in order to make decisions or present definitive information to other parties.
• Use Case: During an exchange of information between parties engaged in argumentation, one party challenges the veracity of presented information and the other party must obtain the provenance of the curated information in order to provide a warrant for the claims made by the information.
• Use Case: An architect is confronted with a problem that calls for the specification of concepts that relate or do not relate with each other with certainty but with probabilistic uncertainties. Other domains have systems that are subject to incomplete, partial knowledge or even conflicting, latent falsehoods.
• Use Case: A stakeholder responsible for contributing to or curating numerous models has too little spare time to poll each model in their scope of responsibility; this stakeholder needs to be notified when an area of interest within a particular model is subject to access or modification by selected individuals or communities of interest.
• Use Case: Two or more stakeholders are collaborating on a common model yet are not present in the same actual meeting place. Lacking body language clues, the stakeholders need avatars of the peers’ presence within the shared model.
• Use Case: A community of stakeholders with differing permissions to view, modify, and relate information form a joint venture that exploits their respective capabilities to solve a complex problem. Meanwhile, the providers of information retain their information confidentiality rights.
• Use Case: An organization is requested to describe, present, or instantiate a system that was created some past time even perhaps with different knowledge tools and by individuals no longer associated with the organization. During such a representation, the organization is requested to demonstrate the differences between the current systems and the legacy systems.
• Use Case: An enterprise-scale team which aggregates functional and domain teams from a variety of corporations, even a variety of cultures and sovereignties, works contemporaneously and serially on a common problem yet at different lifecycle phases, different levels of abstraction, in different disciplines, and with different information access rights.

Emergent Technologies and Tactics

The following technologies or tactics are emerging from the state of the art of model management and of information repositories and show promise of being efficacious in offering the aforementioned ideal capabilities.

• Resource Description Framework (RDF) expression of information
• RDF Triplestores
• N-Quads for RDF triples with statement-specific Provenance context
• Data Distribution Service (DDS) publish-subscribe services
• Google Drive collaborative editing and presence avatars
• Notification services such as Real Simple Syndication (RSS), Short Message Service (SMS), and Twitter
• Role-based Access Control (RBAC)
• eXtensible Access Control Markup Language (XACML)