Description
This is a presentation explains the need of modernization and challenges involved in the transformation.
Legacy System Modernization
Agenda
?
? ? ? ?
Legacy System Overview
Modernization Objectives Modernization - Challenges & Approach Modernization - Process Overview Summary
Legacy System Overview
?
Registration System – used for registration processes and transaction
settlement by Registrars. The system was developed in VAX Basic with RMS data files. It was based on Open VMS platform and uses VMS Shadowing for Disaster Recovery (1970). The modernization objective was to enhance the system to improve current processes and support new requirements, both internal and external.
?
?
Why Modernization was needed?
“A legacy information system is any information system that significantly resists modification and evolution to meet new and constantly changing business requirements.” :~ Brodie and Stonebraker
?
Characteristics of legacy information systems:
? large, millions of lines of code ? geriatric, often more than 10 years old ? written in legacy languages like COBOL/BASIC etc ? built around legacy database systems or files ? autonomous, poorly linked to other applications ? mission-critical, essential to business operations
? ? ? ? ?
Upgrading/replacing Legacy Systems is nightmare Maintaining systems are very costly and not easy Interfacing a new system to legacy systems a big problem Unavailability of hardware and software (Operating System) support Shrinking skill-pool for maintenance staffs
Key Customer Objectives
?
Obsolescence
?
? ? ?
Flexibility to integrate with other system
Increased efficiency, business performance Disaster Recovery Capability Empowering clients with sophisticated web-based reports and management information Workflow based solution, facilitating measurement, recording and monitoring of customer and regulatory service levels
?
?
Modernization within budgeted costs & timescales
Challenges
?
Paradigm shift from Procedural Language to an Object Oriented
structure.
?
Data Access from RMS Flat files to Oracle
?
?
Dynamic Screen Generation to Static Screens (1400 screens)
Optimize system to support re-engineered business processes
Transformation Map
From User Interface Business Logic Jobs Data Store Communication Integration SMG Screens BASIC programs Job control RMS Files Proprietary
To VB.NET Screens .NET components .NET Scheduler Oracle RDBMS BizTalk Server
Approach for Transformation
?
Two-phase approach Transformation solution
? Phase – 1 :- Straight Migration ? Phase – 2 :- Re-engineering
?
Straight migration : Platform and language conversion with minimum changes in the application:
? VAX Basic to Visual Basic on .NET (Program Conversion) ? RMS Data-store to RDBMS (Database Conversion) ? VAX to Windows/Web (Operating System re-hosting)
?
Re-engineering : Transformation of the application involving architectural changes:
? ? ? ? Procedural Architecture to Object Oriented Architecture Application database re-modeling Business Process Reengineering (BPR) Incremental transformation and reengineering methodology
Legacy
Legacy
Modernized
Modernized
Legacy
Migration vs. Re-engineering
?
Migration
?
Re-engineering
Benefits of Two-phase Approach
Technical Benefits
? ? ? ? ?
Business Benefits
?
Modular Approach Faster Deployment Tool based Migration Easy Data Migration Reusability of code
Risk-Managed Modernization Approach (RMM)
?
? ? ?
Accurate business logic extraction
Business Process re-reengineering Greater project visibility Quicker payback
?
?
Comprehensive Testing
Automated approach to Business Functionality extraction
?
?
Improved ROI
Dependable schedule & budget estimates User familiarity with new system
?
Possible to Re-architect system to OO and SOA system
?
interface
?
Ease of training to end-users
Why not a Single Step (Big-Bang) Approach
?
Long Project Duration
? Not Possible to hold back Business Critical Changes ? Large amount of functional retrofitting
?
Resources dependency for Legacy System Support for longer duration Testing more difficult
? Language transformation, architectural and business functionality
?
changes
? Original Test case not compatible with New System
? ?
Higher Risk of Project Schedule/Effort Variation Higher Risk of Project Failure
Transformation Process Overview
Legacy Source RMS Data Store Reverse Engineering
Conversion
Logic Extraction Migrated Live System New Reengineered Registration System
Migrated Source
RDBMS Data store
Data Transfer
Database Engineering
Forward Engineering
Migrated Application
Integrated System
Phase 1- Migration
Phase 2 – Reengineering
Re-engineering Process Cycle
Migrated Application Identify Application Modules Merged Intermediate Reengineered Application Final Reengineered Application
Reengineering Module Selection
Reverse Engineering (Tool Based) Merged Component Diagrams Class Diagrams Dynamic Diagrams
Business Rule Extraction
Business Logics
Integrate Modified Modules
Forward Engineering
Reengineered Module
Deployment Strategy
? ?
Business continuity must be preserved during deployment. New technology demonstration (using prototype) by early deployment and testing on production server.
?
Stable, full-featured, tested versions software to be deployed and adequate training, acceptance testing to be done at least 4 to 6
weeks prior to deployment.
Benefits of the Modernization Approach
? ?
Clearer project visibility to the customer. The platform migration phase enabled the application to be up and running within a shorter time span in the new environment.
?
Subsequent Reengineering was carried out in an incremental manner, taking each module at a time; this facilitated better controlled testing and implementation.
?
Business continuity was preserved during deployment. Total application
shutdown was minimized.
?
The modernized application having rich user-interface and functionality was up and running within scheduled time and budgeted cost
Summary
?End-to-End
solutions ?Lowering Total Cost of Ownership ?Improved Service Levels ?Domain knowledge support ?Support to BPR activities ?Post go-live support ?Agreed Performance ?Dependable & efficient transformation under Firm Schedule and Price
Triple A Benefit Accurate set of tools Adaptive processes / methodologies Assured delivery on Budget & Schedule
THANK YOU
doc_194190904.pptx
This is a presentation explains the need of modernization and challenges involved in the transformation.
Legacy System Modernization
Agenda
?
? ? ? ?
Legacy System Overview
Modernization Objectives Modernization - Challenges & Approach Modernization - Process Overview Summary
Legacy System Overview
?
Registration System – used for registration processes and transaction
settlement by Registrars. The system was developed in VAX Basic with RMS data files. It was based on Open VMS platform and uses VMS Shadowing for Disaster Recovery (1970). The modernization objective was to enhance the system to improve current processes and support new requirements, both internal and external.
?
?
Why Modernization was needed?
“A legacy information system is any information system that significantly resists modification and evolution to meet new and constantly changing business requirements.” :~ Brodie and Stonebraker
?
Characteristics of legacy information systems:
? large, millions of lines of code ? geriatric, often more than 10 years old ? written in legacy languages like COBOL/BASIC etc ? built around legacy database systems or files ? autonomous, poorly linked to other applications ? mission-critical, essential to business operations
? ? ? ? ?
Upgrading/replacing Legacy Systems is nightmare Maintaining systems are very costly and not easy Interfacing a new system to legacy systems a big problem Unavailability of hardware and software (Operating System) support Shrinking skill-pool for maintenance staffs
Key Customer Objectives
?
Obsolescence
?
? ? ?
Flexibility to integrate with other system
Increased efficiency, business performance Disaster Recovery Capability Empowering clients with sophisticated web-based reports and management information Workflow based solution, facilitating measurement, recording and monitoring of customer and regulatory service levels
?
?
Modernization within budgeted costs & timescales
Challenges
?
Paradigm shift from Procedural Language to an Object Oriented
structure.
?
Data Access from RMS Flat files to Oracle
?
?
Dynamic Screen Generation to Static Screens (1400 screens)
Optimize system to support re-engineered business processes
Transformation Map
From User Interface Business Logic Jobs Data Store Communication Integration SMG Screens BASIC programs Job control RMS Files Proprietary
To VB.NET Screens .NET components .NET Scheduler Oracle RDBMS BizTalk Server
Approach for Transformation
?
Two-phase approach Transformation solution
? Phase – 1 :- Straight Migration ? Phase – 2 :- Re-engineering
?
Straight migration : Platform and language conversion with minimum changes in the application:
? VAX Basic to Visual Basic on .NET (Program Conversion) ? RMS Data-store to RDBMS (Database Conversion) ? VAX to Windows/Web (Operating System re-hosting)
?
Re-engineering : Transformation of the application involving architectural changes:
? ? ? ? Procedural Architecture to Object Oriented Architecture Application database re-modeling Business Process Reengineering (BPR) Incremental transformation and reengineering methodology
Legacy
Legacy
Modernized
Modernized
Legacy
Migration vs. Re-engineering
?
Migration
?
Re-engineering
Benefits of Two-phase Approach
Technical Benefits
? ? ? ? ?
Business Benefits
?
Modular Approach Faster Deployment Tool based Migration Easy Data Migration Reusability of code
Risk-Managed Modernization Approach (RMM)
?
? ? ?
Accurate business logic extraction
Business Process re-reengineering Greater project visibility Quicker payback
?
?
Comprehensive Testing
Automated approach to Business Functionality extraction
?
?
Improved ROI
Dependable schedule & budget estimates User familiarity with new system
?
Possible to Re-architect system to OO and SOA system
?
interface
?
Ease of training to end-users
Why not a Single Step (Big-Bang) Approach
?
Long Project Duration
? Not Possible to hold back Business Critical Changes ? Large amount of functional retrofitting
?
Resources dependency for Legacy System Support for longer duration Testing more difficult
? Language transformation, architectural and business functionality
?
changes
? Original Test case not compatible with New System
? ?
Higher Risk of Project Schedule/Effort Variation Higher Risk of Project Failure
Transformation Process Overview
Legacy Source RMS Data Store Reverse Engineering
Conversion
Logic Extraction Migrated Live System New Reengineered Registration System
Migrated Source
RDBMS Data store
Data Transfer
Database Engineering
Forward Engineering
Migrated Application
Integrated System
Phase 1- Migration
Phase 2 – Reengineering
Re-engineering Process Cycle
Migrated Application Identify Application Modules Merged Intermediate Reengineered Application Final Reengineered Application
Reengineering Module Selection
Reverse Engineering (Tool Based) Merged Component Diagrams Class Diagrams Dynamic Diagrams
Business Rule Extraction
Business Logics
Integrate Modified Modules
Forward Engineering
Reengineered Module
Deployment Strategy
? ?
Business continuity must be preserved during deployment. New technology demonstration (using prototype) by early deployment and testing on production server.
?
Stable, full-featured, tested versions software to be deployed and adequate training, acceptance testing to be done at least 4 to 6
weeks prior to deployment.
Benefits of the Modernization Approach
? ?
Clearer project visibility to the customer. The platform migration phase enabled the application to be up and running within a shorter time span in the new environment.
?
Subsequent Reengineering was carried out in an incremental manner, taking each module at a time; this facilitated better controlled testing and implementation.
?
Business continuity was preserved during deployment. Total application
shutdown was minimized.
?
The modernized application having rich user-interface and functionality was up and running within scheduled time and budgeted cost
Summary
?End-to-End
solutions ?Lowering Total Cost of Ownership ?Improved Service Levels ?Domain knowledge support ?Support to BPR activities ?Post go-live support ?Agreed Performance ?Dependable & efficient transformation under Firm Schedule and Price
Triple A Benefit Accurate set of tools Adaptive processes / methodologies Assured delivery on Budget & Schedule
THANK YOU
doc_194190904.pptx