Web Service Composition via Copy Rules and State Segmentation

Solution Overview

Problem

Existing methods for composing Web services are inefficient in terms of computation time and memory usage, as they often require processing all possible combinations of states, and struggle with non-deterministic behaviors and failures, which can lead to deviations from intended execution paths.

Innovation Solution

A system and method that uses Web service representations to generate copy rules describing efficient sequences of transitions from initial to final states, incorporating abstract state machines for orchestration, and handling deviations by identifying recovery goals and transitions, allowing for efficient simulation and execution of composite Web services.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If all possible combinations of states are processed to compose Web services, then completeness of service composition is improved, but computation time and memory usage increase significantly

Engineering Contradiction:

Improvecompleteness of service compositionVSAvoidcomputation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent segments the state space by identifying and separating reachable states from unreachable ones using static analysis. By dividing the composition problem into reachable and unreachable state components, the system processes only relevant state combinations, dramatically reducing computation time while maintaining completeness for reachable states.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary static analysis to compute reachable states before executing the Web service composition. This preliminary action identifies which state combinations are actually attainable, allowing the system to pre-filter the search space and avoid processing impossible or unreachable state transitions during runtime.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If all possible combinations of states are processed to compose Web services, then completeness of service composition is improved, but memory usage increases significantly

Engineering Contradiction:

Improvecompleteness of service compositionVSAvoidmemory usage

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent segments the state space by identifying and separating reachable states from unreachable ones using static analysis. By dividing the composition problem into reachable and unreachable state components, the system processes only relevant state combinations, dramatically reducing computation time while maintaining completeness for reachable states.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary static analysis to compute reachable states before executing the Web service composition. This preliminary action identifies which state combinations are actually attainable, allowing the system to pre-filter the search space and avoid processing impossible or unreachable state transitions during runtime.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If traditional composition methods are used to handle non-deterministic behaviors, then coverage of failure scenarios is improved, but ability to maintain intended execution paths deteriorates

Engineering Contradiction:

Improvecoverage of failure scenariosVSAvoidexecution path consistency

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent incorporates feedback mechanisms through copy rules that monitor execution states and automatically trigger recovery transitions when deviations are detected. The system continuously compares actual execution paths against intended paths and uses feedback from state monitoring to activate appropriate recovery actions, maintaining execution consistency while handling non-deterministic behaviors.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent prepares recovery transitions in advance by pre-defining copy rules for various failure scenarios. Before actual failures occur, the system establishes contingency plans that automatically activate when specific deviation conditions are met, cushioning against the impact of non-deterministic behaviors and maintaining execution path stability.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentUS7979361B2Composition of web services using representations

Publication Date: 2011.07.12 SAP SE

AI summary

A system for composing Web services may include a goal determiner unit and a composer unit. The goal determiner unit may be configured to access a primary goal of final states of Web service representations. The composer unit may be configured to compute a set of transitions from initial states of the Web service representations to the primary goal, compute intermediate states of one or more Web service representations, and generate a copy rule of the set of transitions, the copy rule having a condition part that specifies the intermediate states and a portion of the final states of the primary goal and an activity part that includes assignments of input variables consumed by transitions from the intermediate states.