What are the common traditional structured development models and what are their characteristics?

Iterative model, spiral model, waterfall model

1, structured system development method (also known as "life cycle method")

(1) Advantages: Starting from the whole system, it emphasizes the "top-down" analysis and design under the overall optimization condition, which ensures the integrity of the system and the consistency of goals; Follow the principle of customer first; Strictly distinguish the stages of system development; The results of each stage are the foundation of the next stage, which is convenient for the management and control of system development; Document standardization, establish standardized documents according to engineering standards.

(2) Disadvantages: user quality or communication problems between system analysts and managers; The development cycle is long and it is difficult to adapt to environmental changes; For the system with low structure level, it is difficult to lock the functional requirements at the early stage of development.

(3) Scope of application: It is mainly suitable for the development of large-scale and highly structured systems.