Rich Service Model

Policies

Policy EvaluatorRequestor Fulfiller

Generic Workflow

Requestor

Fulfiller

Alternate Fulfiller

1

2

1

4

2 3

2'

3' Policy Evaluator(injected at

runtime) If User in Researchers then Fulfiller

else AlternateFulfiller

Policies

Policy Evaluator

Requestor Fulfiller

Generic Workflow

Requestor

Fulfiller

Alternate Fulfiller

1

3

1

2

54'

5' Policy Evaluatorreturns service to

execute

Router2

4 36

4Router

If User in Researchers then [Fulfiller]

else [AlternateFulfiller]

Policy-driven DevelopmentJust-In-Time Workflow Composition

Barry Demchak (bdemchak@ucsd.edu) & Ingolf KrügerCalifornia Institute for Telecommunications and Information Technology, San Diego Division

Context

Cyberinfrastructure (CI)† †

• 100s of stakeholders (e.g., producers, consumers, operators, etc.)

• Stakeholders opt in only when CI satisfies their requirements

• CIs have long delivery times

Solution

Policy• Injected at specific workflow location• Decision expressed in Domain-

Specific Language (DSL1)• Provides alternate workflow(s)

Results

Benefits• Rapid requirement realization

(on live system)• Enable stakeholders to articulate

requirements as policies• Enable complex/compound policies

Future Work• Policy authoring system2,3

• Verify completeness/correctness4 using CPN Tools5

• Maintain system consistency• Secure policy deployment

This material is based upon work supported by the National Institutes of HealthUnder Grant Nos 1U01CA130771-01 (Project PALMS: Kevin Patrick, PI) and U54 HL108460

f

† †Cyberinfrastructures (CI) f

f

†PALMS ReferencesPhysical Activity Location Measurement System to understand where activity-related energy expenditure occurs in humans as a function of time and space. Harvests data from wearable devices on small and large scales, provides framework for research and analysis, and has ultimate goal of discovering methods for engineering better health.

An Internet-based research computing environment that supports data acquisition, data storage, data management, data integration, data mining, data visualization, and other computing and information processing services. Different stakeholders produce, consume, manage, and govern a CI, and their requirements must be simultaneously met or else the integrity of the CI degrades.

1. M. Fowler. Domain-Specific Languages. Boston, MA: Addison-Wesley, Pearson Education, Inc. Sept 2010.2. T. Lodderstedt, D. Basin, and J. Doser. SecureUML: A UML-Based Modeling Language for Model-Driven Security. Proceedings of the

5th International Conference on The Unified Modeling Language. pp426-441. Springer Verlag, 2002.3. A. Bhattacharjee and R. Shyamasundar. Activity Diagrams: A Formal Framework to Model Business Processes and Code Generation.

Journal of Object Technology. Vol 8, No 1, Jan 2009.4. J. Juerjens. Security Systems Development with UML. Springer-Verlag Berlin Heidelberg, 2003.5. K. Jensen and L. Kristensen. Coloured Petri Nets: Modeling and Validation of Concurrent Systems. Berlin: Springer-Verlag. 2009.6. M. Arrott, B. Demchak, V. Ermagan, C. Farcas, E. Farcas, I. H. Krüger, and M. Menarini. Rich Services: The Integration Piece of the

SOA Puzzle. In Proceedings of the IEEE International Conference on Web Services (ICWS), Salt Lake City, Utah, USA. IEEE, Jul. 2007, pp. 176-183.

Sensor Data

Techniques

Service Oriented Architecture-based execution & deployment• Leverage standard patterns5:

strategy, messaging, routing, & composite pattern

• Leverage role-based interaction, choreography & interceptor techniques

• High availability, reliable, scalableModel-driven engineering

• Refinement follows Rich Service6 decomposition & logical/deployment transformation

• Composition based on Systems-of-Systems principles

PALMS† Case Study

Data Storage Calculations Visualization

Overall Requirements

Problem

More stakeholders requirements churn even longer delivery times unhappy stakeholders∴ lower likelihood CI will satisfy

community requirements

Insight

Compose new workflows onto existing workflows at runtime• Access control, data stream filtering• Feature addition/deletion

Conceptual