the difference between waterfall model of SDLC and spiral model of SDLC.
Diff btw waterfall model and spiral model Waterfall model In this, the customer is not involved When the development process shifts to the next stage, there is no going back. Waterfall allows no such scope. Has sequential progression, with clear documentation of the entire process. Least flexible model. It is document driven. In Waterfall model each step is distinct. The output is not known unless all stages are over. s/w developer knows the actual problem. Has five main phases namely; requirement, design, implementation, verification and maintenance. spiral model In this, the customer is involved in the s/w dvlpmnt from the word go. Since there are different iterations, it is rather easier to change the design and make the s/w feasible. Here, one can revisit the diff phases of s/w dvlpmnt as mny tyms as poss. Has complex model. The most flexible model. Does not require document. In spiral model we dont define everything in detail at very beginning. The final output is known from the beginning. s/w developer does not know the problem. Has four main stages which are objectives, identity, dvlpmnt and planning.