Abstract: Software DFT (design-for-testability) is introduced as a new concept for solving problems in protocol developing course and testing course. Some DFT methods about communication software are discussed then. Setcontrol points on SAP (service access point) and add independent test-sequenceintroducer for controlling the system's movement. Set observation points on SAP and use simple output statements as observation apparatus for observing the system'smovement. Use test switches for testing any parts of software that you care about. These methods are very simple. Additional software caused by DFT is very little and doesn't affect the system's normal movement, but they can improve the software testability greatly.

Key words: software testing, design-for-testability, test points, test apparatus