Short note on Software Re-engineering

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 Software Re-engineering

- Software Re-engineering is a process of software development that is done to improve the maintainability of a software system. 

- Re-engineering is the examination and alteration of a system to reconstitute it in a new form. This process encompasses a combination of sub-processes like reverse engineering, forward engineering, reconstructing, etc.

- Re-engineering is the reorganizing and modifying of existing software systems to make them more maintainable. 


Objectives of Re-engineering: 

  • To describe a cost-effective option for system evolution.
  • To describe the activities involved in the software maintenance process.
  • To distinguish between software and data re-engineering and to explain the problems of data re-engineering.

Steps involved in Re-engineering: 

  • Inventory Analysis 
  • Document Reconstruction 
  • Reverse Engineering 
  • Code Reconstruction 
  • Data Reconstruction 
  • Forward Engineering 


Re-engineering Cost Factors: 

  • The quality of the software to be re-engineered
  • The tool support available for re-engineering
  • The extent of the required data conversion
  • The availability of expert staff for re-engineering

Advantages of Re-engineering: 

  • Reduced Risk: As the software is already existing, the risk is less as compared to new software development. Development problems, staffing problems, and specification problems are lots of problems that may arise in new software development. 
  • Reduced Cost:  The cost of re-engineering is less than the cost of developing new software.
  • The revelation of Business Rules:  As a system is re-engineered, business rules that are embedded in the system are rediscovered.
  • Better use of Existing Staff: Existing staff expertise can be maintained and extended to accommodate new skills during re-engineering.

Disadvantages of Re-engineering: 
  • Practical limits to the extent of re-engineering.
  • Major architectural changes or radical reorganizing of the systems data management has to be done manually.
  • The re-engineered system is not likely to be as maintainable as a new system developed using modern software Re-engineering methods. 

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