1. Service Oriented Architectures (SOA): What Users Need to Know.
OGF 19: January 31, 2007
Charlotte, NC
John Salasin, Ph.D,
Visiting Researcher
National Institute for Standards and Technology

2. Purpose(s) Of Workshop
Discuss “Predictive Metrics” that can help SOA system developers determine if project is “on track”
Discuss potential value of a metrology basis for SOAs
How could this be used to better inform design, development, acquisition, operation?
What are the measurement needs wrt:
Consistency supporting reuse
Match to business requirements
Policy / Security
Performance and Behavior
Total Cost of Ownership – Technical Aspects

3. Purpose(s) (of talk)
Introduce potential framework for SOA Predictive Metrics
The start of an ontology of metrics
Provide examples to stimulate Discussion

4. Outline of Talk Claimed advantages of SOA-based systems
Objects of interest
System Components
Enterprise characteristics

5. Claimed advantages of SOA-based systems
Direct mapping between business processes and automated services
Understandability
Simplified reuse
Modifiability/co-evolution/adaptability
Rule/script-based modifications by business managers rather than system experts
Dynamic orchestration mapped to business work flow
Common interaction protocol(s) – often Grid Services
N rather than N x N interface protocols
Standard infrastructure tools/components (e.g., ESB)
Adaptable to heterogeneous platforms
Integrate separately developed “stovepipe” systems
Based on meta-data describing data and services
Enables “smart” systems
Selection of most appropriate process component
Automatic data transformations

6. System Components Business processes Service Components Data
Procedures
Computation/transformation
Accept input (sensing / monitoring)
Business process execution
System health/status (?)
Rules/Policy (including security)
Change / evolution
Connectors / links/ configuration
Work flow / orchestration (and evolution)

7. Enterprise Characteristics
Pervasiveness of function
Size, variation, dispersion
Functional characteristics
Customer requirements
Degree of homogeneity/heterogeneity
Extent of definition / formalization
Value of SOA capabilities to customer(s)
Broader coverage
More current / accurate

8. Dimensions of the Metric Space (Top Down)
Total Cost of Ownership (TCO) is theme
Effort to maintain congruence between business processes and system
Similarity of (formal) representations at highest level
Fit to functional organization of business
System development/modification effort
Automatic generation of checks of correctness for refinement
Use of legacy components (wrapping technology)
Rule/script based specification of, e.g.:
Dynamic orchestration
Rule monitoring and enforcement
Business data monitoring, collection, and triggering action
Monitoring system health / performance

9. Dimensions of the Metric Space (Cont.)
Effectiveness
Usability by all customer(s)
Impact on productivity
Comprehensiveness of information for decisions
Effort to specify/modify information collection and analysis
Evolvability (modification by business managers)
Actual and opportunity costs for deployment and modification
Efficiency
Reliability
Response time
Resource use

10. Potential Taxonomy (Bottom up)
Architecture/Scope
SOA-BP congruence
% of “mappable” functions
Comprehensiveness of service – all info needed?
% info needed by customer provided by system
Scope of events monitored (sensing capabilities)
Notations
SOA-BP documentation allowing analysis (including of policy/procedure effectiveness and efficiency)
Effort writing code/rules/validity checks/data transformations – skill, training
Effort to modify – change propagation across models and in refinement
Scope of events monitored (scripting language)
Utility
Added value of SOA-enabled info (enterprise-wide, timely)
Use by intended customers as function of time
Use and adoption by other organizational units as function of time
Impact on productivity/costs to deliver service or product

11. Potential Taxonomy (Conc.)
Extensibility
Automated service discovery
Ability to combine multiple data and process specifications
SLA specification and enforcement
Anomaly detection and correction, load balancing
Ability to specify multi-step atomic transactions with rollback/recovery mechanisms
Rule consistency checking when changes made
Likelihood of metastasis in organization(s)
Ability to incorporate legacy – wrapping, data reconciliation, data transformation capabilities –overhead for run-time operations
Ability of other units to use services developed for SOA
Organizational "fit“(Percent of services that map to a more global Functional Architecture)

12. Next Steps Extend and validate candidate metrics
Prune and augment candidate set
Improve quantification
Develop metrics ontology
Relationships among measures
controlled vocabulary to describe objects and the relations between them
a grammar for using the vocabulary terms to express something meaningful within a specified domain of interest.

13. How you can help Review draft document to suggest: Provide comments
Useful measures
Additions/deletions
Provide comments