Jawaharlal Nehru Technological University Hyderabad B.Tech III SOFTWARE ENGINEERING Previous Question Paper (January/February - 2023 - R13)

Legacy software refers to older software systems, applications, or technologies that are still in use by an organization despite being outdated or replaced by newer systems. These systems are often critical to business operations, difficult to maintain due to obsolete hardware or programming languages, and frequently lack documentation or support from the original developers.

The Waterfall model is a linear-sequential software development life cycle (SDLC) approach where progress flows steadily downwards through distinct phases. Each phase must be completed and verified before the next phase begins, with no overlapping activities.

The typical phases include:

1. Requirements Analysis: Gathering and documenting all system requirements.
2. System Design: Defining the architecture and hardware/software requirements.
3. Implementation: Coding the software based on the design specifications.
4. Testing: Systematically verifying the software to identify and fix defects.
5. Deployment and Maintenance: Releasing the product and performing ongoing updates or bug fixes.

This model is best suited for projects with stable, well-defined requirements, as it is difficult and costly to return to a previous phase once development has progressed.