Copyright 2002 KLOCwork Solutions Inc. 1 Toward the full-cycle application of ITU-T languages Dr. Nikolai Mansurov Chief Scientist 2 nd March, 2002, Geneva

Copyright 2002 KLOCwork Solutions Inc.1

Toward the full-cycle Toward the full-cycle application of application of ITU-T languagesITU-T languages

Dr. Nikolai MansurovChief Scientist

2nd March, 2002, Geneva


Presentation outlinePresentation outline

1. Introduction to KLOCwork2. Discontinuities in today’s SW engineering space

• Missing ITU notation and recommendation for SW architectures• Gap between methods and tools support for developing new

code and maintaining existing code (including architecture optimization)

• Discontinuity between requirements, architecture design and component implementation

3. Closing the architecture gap: KLOCwork’s experiences in architecture modeling, analysis and optimization

4. Closing another gap: Rapid prototyping with scenarios5. Synergy: The full-cycle application of ITU-T languages6. Conclusions and discussion points


1. Introduction to KLOCwork1. Introduction to KLOCwork

• KLOCwork: Productivity solutions, aimed at helping SW development organizations improve their Architecture Capability Maturity

• Short-term: suite of tools and professional services to• Expose SW architecture problems, quality issues• Explore solutions, architecture clean-up and optimization• Enforce integrity, manage architecture, prevent erosion

• Long-term:• Evolution of existing SW into software product lines• Adoption of state-of-art methodologies• Evolution towards hybrid systems

• Spun out of Nortel Networks (Canada) in March 2001• Based in Ottawa, Canada – Silicon Valley North• Research subsidiary in Russian Academy of Sciences, Moscow• Currently 40 members of staff


Clients and partnersClients and partners


2. Discontinuities in today’s SW engineering space2. Discontinuities in today’s SW engineering space

• SW engineering space: notation perspective• Today’s status• Success stories• Discontinuities in SW engineering space• Discontinuities


SW engineering space: notationsSW engineering space: notations

state-based models(SDL)

scenarios(MSC)

source code(C,C++,CHILL, Java, etc)

execution traces(MSC)

object models(UML)

architecture models(UML?!)

requirements (URN)

behavior structure

detailed

abstract

performance modelsdeployment models

testing models (TTCN)

ITU-T notation exists

Under construction

Legend:

Missing notation ?

???

???


Today’s statusToday’s status

• State-of-art object-oriented analysis and design methodologies (aka UML) and component-based methodologies (e.g. WebSphere, etc.) successfully embrace structure modeling (object models). Methods and tools provide guidance and automated support for• Specification of object models• Code generation from object models

• State-of-art real-time modeling methodologies (e.g. ITU method, Telelogic, Rational Rose RealTime) successfully embrace behavioral modeling (state-based models). Methods and tools provide guidance and automated support for • Specification of state-based models• Analysis and validation of state-based models,• Simulation of state-based models• Code generation from state-based models

• However there exist several discontinuities


Success storiesSuccess stories

NotationTool-supported transitionOther transition

execution

simulation or

validation

real-time modeling tools

state-based models

scenarios

source code

execution traces

object models

architecture models

requirements

code generation

UML tools


Discontinuities in SW engineering spaceDiscontinuities in SW engineering space

state-based models

scenarios

source code

execution traces

code generation

execution

simulation or

validation


object models

UML tools

??? architecture models

requirements

???

???

???

??????

???

???Discontinuity

NotationTool-supported transition


Discontinuities:Discontinuities:

• Notation and methodology recommendation for SW architectures• Lack of guidance in modeling and managing SW architectures of existing SW is a

serious problem for our customers

• Architecture design to component design and implementation Formal modeling of requirements (therefore tool support for early SW engineering stages)

• Requirements to architecture design• Requirements to design (including state-based models)• Tool support for scenarios• Scenarios to state machines• Implementation to analysis and design (the “legacy barrier”):

• Implementation back to architecture design• Implementation back to scenarios• Implementation back to state-based models

• There exists a huge (and growing) gap between method and tool support for developing new code and maintaining existing code


3. Architecture excavation, analysis and optimization3. Architecture excavation, analysis and optimization

Closing the architecture gap: KLOCwork’s experiences in architecture modeling, analysis and optimization

• What is architecture excavation ?• Architecture models used by KLOCwork• Operations on architecture models, supported by KLOCwork

Suite• Architecture Optimization Process• Architecture-centric evolution of existing SW


Architecture Excavation:Architecture Excavation:

Acceleration effect from combined excavation of structure and scenarios

scenarios(MSCs)

Architecture models are precise

source code

architecture model

Initial model is automatically extracted by our Architecture Compiler

detailed

abstract

Architecture excavation is a process of transforming the initial architecture model to achieve more abstraction and remove accidental dependencies

Abstraction of scenarios is driven by abstraction of the architecture model

The excavated architecture model should be simple enough to communicate and therefore – to manage; it can be analyzed and then optimized


Package Diagram

Architectural Package

Architectural Package

Dependencies between packages

Dependencies between a package

and environment

100 15 3number of relations

ModelProject

KLOCwork architecture modelsKLOCwork architecture modelslist of relations / interfaces

Containment tree

double-click

symbolSymbol on an object

diagram

source code

double-click

File

relation in source code

double-click


Package or Object Diagram

Architectural Package (block)

Architectural Package (block)

Dependencies between blocks

Dependencies between blocks and environment

100 15 3

•Select type of relationships to view•Change selections•List relationship details

Model

Project•Create•Build•Delete •Open

•Save•Enable others to view•Delete

•Group/Ungroup •Cut/Paste•Add•Delete•Move•Resize•Rename•Go inside block•Go up in hierarchy

•Show flowchart•Show definition•Show usage•Show messaging•Show inheritance•Block description•Show attributes•Show users•Show uses

Operations on KLOCwork architecture modelsOperations on KLOCwork architecture models

Main operations supporting architecture excavation are group/ungroup and cut/paste. Dependencies between packages are recalculated on-the-fly as symbols and sub-packages are moved.


Architecture Optimization Process:Architecture Optimization Process:

Launch

Review

Assessment

Cleanup Integration

Software DNA Extraction

Architecture Excavation

Conceptual Analysis

Robustness Analysis

Analysis phase

Implementation phase

Step applied to each component (in parallel)

Step applied to the whole system

Phase


Architecture-centric evolution of existing SWArchitecture-centric evolution of existing SW

existing code

Notation

Tool-supported transition

4. Clean-up

scenarios(H)MSC

architecture models

1. Architecture excavation

Architecture of the software is improved as the result of the optimizations. This results in better SW engineering productivity

Integrity of the SW needs to be enforced to prevent architecture erosion

5. Enforce integrity of the architecture

3. Optimization

2. Architecture analysisIn the long-term, evolution should be directed by a certain goal, for example evolution into a software product line


4. Closing another gap: rapid prototyping with scenarios4. Closing another gap: rapid prototyping with scenarios

• KLOCwork MSC to SDL Synthesizer• Scenario support extends applicability of modeling tools to

earlier phases of the SW engineering• Use Cases for the KLOCwork MSC to SDL Synthesizer• KLOCwork Bridge product family


KLOCwork MSC to SDL SynthesizerKLOCwork MSC to SDL Synthesizer

• Supports ITU-T Message Sequence Charts (MSC) as scenario notation

• Supports ITU-T High-level Message Sequence Charts (HMSC) a composition language

• Supports SDL data extensions to MSC scenarios• Automatically generates state-based models ITU-T Specification and

Description Language (SDL)• Both structure, behavior and data definitions are generated• Complete & correct SDL, ready to simulate and validate• Readable plain SDL is generated• Flexible type-based SDL is generated

• Seamlessly integrates with Telelogic Tau environment • Brings SDL tools to early phases of the development process• Provides complete graphical environment for rapid prototyping with

scenarios


Scenario support expands applicability of modeling tools Scenario support expands applicability of modeling tools


source code

execution traces

code generation

execution

simulation or validation


scenarios(H)MSC

simulation or validation

KLOCwork MSC to SDL Synthesizer

code generation architecture models

requirements models

Notation



Use Cases for the KLOCwork MSC to SDL SynthesizerUse Cases for the KLOCwork MSC to SDL Synthesizer

• Jump-start SDL projects with MSCs• Use MSCs to rapidly prototype functional

requirements• Use MSCs to perform early fault detection• Use MSCs to generate test cases (“system slice”)• Use MSCs to architecture definition and validation

(“executable architectures”)• Use MSCs and data extensions to design

components• Use MSC to SDL Synthesizer for training SDL


The KLOCwork Bridge product familyThe KLOCwork Bridge product family

Type-based SDL

(H)MSCwith SDL data

(H)MSC Analyzer

Synthesizer

Event Automata

Tcl API

Plain SDL

code generator

User Defined

KLOCwork MSC to SDL Synthesizer

Java

KLOCwork Bridge for Java


5. Synergy: The full-cycle application of ITU-T languages5. Synergy: The full-cycle application of ITU-T languages

“Full-cycle” application of ITU-T languages embraces both the existing code and the early SW engineering phases. In other words, the full-cycle addresses the discontinuities in SW engineering space. We believe, that if we achieve the full-cycle applicability of ITU-T languages, this will dramatically improve their adoption.

From KLOCwork’s perspective, the full-cycle should support evolution of existing SW, should be architecture-centric and scenario-based.

• Architecture-centric evolution of existing software• Scenario-based reconstruction of SDL models of existing SW• Evolution of existing SW: hybrid systems as an architecture

concept to support using state-of–art methodologies to develop new features to existing code


Architecture-centric evolution of existing SWArchitecture-centric evolution of existing SW

Notation


This is an important problem for real-time industry !

scenarios(H)MSC

existing code

architecture models

4. Clean-up

3. Optimization


5. Enforce integrity of the architecture

2. Architecture analysis

Currently KLOCwork is using proprietary notation for modeling architectures of existing SW, because an ITU-T notation does not exist


Scenario-based reconstruction of SDL models of existing SWScenario-based reconstruction of SDL models of existing SW


scenarios(H)MSC

source code

execution traces

execution

code generation

architecture models

Notation


???

Dynamic approach to extracting scenarios from existing SW. Execution is driven by legacy test suites. Source code needs to be instrumented according to an architecturally significant probe placement strategy.

Static approach to extracting scenarios from existing SW. Is driven entirely by architecture excavation.

Dynamic approach is relatively easy to implement but it may result in large information spaces. Static approach requires more effort, however it guarantees a smaller number of architecturally significant scenarios. The two approaches can be combined.

The resulting SDL model can be used for verification purposes, to generate test cases, or for evolutionary purposes


Evolution of existing SW: hybrid systemsEvolution of existing SW: hybrid systems


scenarios(H)MSC

existing code

architecture models

Notation


generated code

5. Code generation

3. Clean-up

2. Optimization


Hybrid system

4. State-of-art methodologies are used to develop new features to existing code

Architecture of existing code needs to be improved to allow integration with generated code

Hybrid systems require high level of Architecture Capability Maturity. The architecture of the system needs to be tightly managed and optimized.

Hybrid systems require advanced adaptive code generation techniques


6. Conclusions and discussion6. Conclusions and discussion

• Conclusions• Discussion questions• Discussion


Conclusions:Conclusions:

1. KLOCwork is committed to work together with ITU-T to develop better languages & methodologies for SW engineering space, and to promote their wider adoption by the industry

2. Full-cycle application of ITU-T languages will improve adoption3. There exist certain discontinuities in today’s SW engineering space

that prevent the full-cycle application of ITU-T languages:• Missing ITU-T notation and recommendation for SW architectures• The “legacy barrier”: lack of systematic recommendations and tool

support to (re-)construct formal models of existing SW• Gap between methods and tools support for developing new code and

maintaining existing code (including architecture optimization)• Discontinuity between requirements, architecture design and

component implementation

4. The KLOCwork MSC to SDL Synthesizer allows rapid prototyping with (H)MSC scenarios. We believe, this closes the gap with support for early SW engineering phases and will improve adoption of ITU-T notations

5. Full-cycle: evolutionary, architecture-centric and scenario-based.


Discussion questions:Discussion questions:

• Should ITU-T SG17 recommend a separate SW architecture notation and methodology ?• Is it not already covered by SDL and MSC ?• ODP ?• All SG17 recommendations combined ?

• Should ITU-T SG17 recommend a methodology to model, manage and optimize existing SW architectures ?

• Should ITU-T recommend methodology for the evolution of existing SW ?• Strategic reuse recommendations• Software product lines recommendations• Best practices and architecture patterns for real-time SW

• Are there any other gaps in ITU-T suite of recommendations for SW engineering ?

• How to promote rapid prototyping with (H)MSC scenarios ?• Who would be the early adopters and champions ?• (see some use cases in addendum)


Addendum:Addendum:

Use cases for the KLOCwork MSC to SDL Synthesizer • Jumpstart an SDL project

• Rapidly prototype requirements

• Automatically perform early fault detection

• Automatically generate test cases

• Define and validate architecture

• Design components• Train team members


Jump start your next SDL projectJump start your next SDL project

MSC to SDL Synthesizer can be used to jumpstart your SDL project. Start with few easy to understand scenarios and MSC to SDL Synthesizer will automatically generate a complete SDL specification that is ready to run in Telelogic Tau• Start Telelogic TAU tool• Use Telelogic MSC Editor (MSCE) tool to create MSC diagrams• Use Telelogic HMSC Editor (HMSCE) tool to create High-level

MSC diagram(s)• Run KLOCwork MSC to SDL Synthesizer to produce the SDL

model, corresponding to your (H)MSC model• Use Tau tool to review and simulate the model• Refine the (H)MSC model and re-synthesize the SDL model• Continue SDL project by further refining the generated SDL

model


Use MSCs to rapidly prototype requirementsUse MSCs to rapidly prototype requirements

Jumping into coding too early and not understanding the requirements can result in developing a product that does not meet customer expectations. By using scenarios you can describe functional requirements in an easy to understand format that can be discussed with non-technical stakeholders. • Use Telelogic MSC and HMSC Editors to capture functional

requirements as scenarios, focus on the interaction between your system and its environment

• Simulate your (H)MSC requirements model by using the KLOCwork MSC to SDL Synthesizer and Telelogic Simulator GUI

• When you notice inconsistencies in the prototype go back to your MSC tool, add more scenarios to solve the problem

• Consider co-design on the user interface prototype and scenarios• Review scenarios with customers• Repeat this process until you are satisfied with your prototype


Use MSCs to perform early fault detectionUse MSCs to perform early fault detection

Even when the goals of your project do not include building an SDL model, the KLOCwork MSC to SDL Synthesizer can be used for systematic validation of MSC scenario models. The synthesized SDL model can be analyzed using state-of-the-art state space exploration. Validation process automatically discovers certain faulty behaviors, such as deadlocks, or failed communication. These faulty behaviors are represented as scenarios using the MSC tool. Anomalies in the behavior of the synthesized model usually reflects problems or inconsistencies in the original MSC model.• Use Telelogic MSC and HMSC Editors to capture functional


• Run KLOCwork MSC to SDL Synthesizer to produce the SDL model, corresponding to your (H)MSC model

• Use Tau Validator tool to validate the synthesized SDL model• Review Tau Validator reports• Update the input scenario model


Use MSCs to generate test casesUse MSCs to generate test cases

MSC to SDL Synthesizer can be used to automatically produce test cases as early as at the requirements definition phase. During scenario modeling, the black-box behavior of the system under development is described by specifying desired interactions between the system and its environment. Thus the scenario model contains both the description of the system and the description of the environment of the system. The MSC to SDL Synthesizer can be applied to selectively produce a partial SDL model only for the environment part of the requirements definition. • Use Telelogic MSC and HMSC Editors to capture functional


• Run KLOCwork MSC to SDL Synthesizer to produce the partial SDL model, corresponding to your (H)MSC model – the so-called MSC model slice

• Implement the system• Provide adaptor between the implementation and the slice• Use the synthesized MSC model slice and test environment


Use MSCs for architecture definition and validationUse MSCs for architecture definition and validation

Automatic synthesis can help address the discontinuity between requirements modeling and architecture design. By specifying the so-called subsystem scenarios that describe collaboration between the major architectural components you can create an executable architecture model. • Use Telelogic MSC and HMSC Editors to capture

collaborations between subsystems• Scenarios can be developed concurrently for different subsystems

and then assembled using the Synthesizer• System scenarios are decompositions of the requirements

scenarios• Run KLOCwork MSC to SDL Synthesizer to produce the SDL

model, corresponding to your (H)MSC model• Use the Telelogic SDL Editor to review the SDL block diagram• Use the Telelogic Simulator to explore your “executable

architecture model”• Use Telelogic Tau Validator to look for faults


Use MSCs to design componentsUse MSCs to design components

Automatic synthesis can help address the discontinuity between architecture design and component design. By specifying the component collaboration scenarios you can prototype implementations of individual components. • Use Telelogic MSC and HMSC Editors to capture component

collaborations, focusing at one component at a time • Scenarios can be developed concurrently for different components

and then assembled using the Syntehsizer• Component scenarios are decompositions of the subsystem scenarios• Expect to use data extensions together with scenarios

• Run KLOCwork MSC to SDL Synthesizer to produce the SDL model, corresponding to your (H)MSC model

• Use the Telelogic SDL Editor to review the SDL block diagram• Use the Telelogic Simulator to explore your component

implementations• Use Telelogic Tau Validator to look for faults• Generate code for each component


Use MSC to SDL Synthesizer for training SDLUse MSC to SDL Synthesizer for training SDL• SDL is a complex language and most people find it easier

to understand MSC scenarios than SDL. What you can do is explain a scenario to a student. Then import scenario into the MSC to SDL tool to automatically create the corresponding SDL model. Now the student can learn SDL much quicker by observing the automatically synthesized SDL for an already familiar scenario.• Use Telelogic MSC and HMSC Editors to capture an interesting

scenario• Explain this scenario to the student• Explore the behavior of the scenario using the “Simulate

MSCs” feature of the KLOCwork MSC to SDL Synthesizer• Run KLOCwork MSC to SDL Synthesizer to synthesize the

corresponding SDL model• Let the student explore the synthesized SDL model• Let the student explore the behavior of the synthesized SDL

using the Telelogic Simulator

Documents

Copyright 2002 KLOCwork Solutions Inc. 1 Toward the full-cycle application of ITU-T languages Dr. Nikolai Mansurov Chief Scientist 2 nd March, 2002, Geneva