With the real examples, this paper gives the concept of modularization in SPC exchange software design, as the top-down step-wise refinement disign and dataflow-oriented design method.

• 本文结合实例,阐述电话交换系统中自顶向下、逐步求精及面向数据流的软件设计方法,同时探讨了交换软件模块的独立性问题。