1. Re- engineeniering

2. Forward engineering: Re-engineering:
Starts with system specifications and evolves the design & implementation of a new system
Re-engineering:
Starts with an existing system & the development process for the replacement is based on understanding and transforming the original system.

3. Re-engineering Legacy program Structured modularized
version of the program

4. Activities performed during Re-engineering
Source code translation:
Old language  Modern version language
Reverse engineering:
Documentation. (After analyzing the program)
Program structure improvement:
Control structure analyzed and modified to make it easier to read and understand

5. Program modularization:
Related parts of the program are grouped together and where appropriate, redundancy is removed. In some cases, this stage may involve architectural transformation where a centralised system extended for a single computer is modified to run on a distributed platform.
Data re-engineering:
The data processed by the program is changed to reflect program changes

6. Re-engineering Process
Program Documentation
Original program
Reverse engineering
Program Modularization
Source code translation
Modularized Program
Original data
Program structure improvement
Data Re-engineering
Structured Program
Re-engineered Data

7. Factors affects Re-engineering cost
The quality of the software
The tool support available
The extent of data conversion required
The availability of expert staff

8. Other Approaches for software development
Personal Software Process (PSP)
Team Software Process (TSP)