In this approach, both the systems are run in parallel for a specific period of time. During the period of if any serious problems were identified while using the new system, the new system is dropped and the older system is taken at the start point again.In this approach, the existing system is converted to the new system abruptly, some times over a weekend or even overnight. The old system is used until a planed conversion day. There exist no parallel activities.In this approach, a working version of the system is implemented in one art of the organization such as a single work area or department. When the system is deemed complete it is installed through out the organization either all at once (direct cut-over) or gradually (phase-in).
Analysis is the detailed study of the various operations performed by a system and their relationships within and outside of the system. A key question is: What must be done to solve the problem' Once aspect of analysis is defining the boundaries of the system and determining whether or not candidate system should consider other related system. During analysis, data are collected on the available files, decision points and transactions handled by the present system.Software Requirement Specification is the starting point of software developing activity, as system grew more complex it became evident that the goal of the entire system cannot be easily comprehended. Hence the need for the requirement phase arose. ...Show more