Use Case Trail

Use cases²³ are implemented in various components such as subsystems, processes, modules, and source code files. Most of the time with good tracing implementation we are able to see Use Case Trails: log messages corresponding to use case scenarios. For simple systems one log may fully correspond to just one use case, but for complex systems, especially distributed client-server ones, there may be several use case instances present simultaneously in one log. One way to disentangle them in the absence of UCID (Use Case ID) or some other grouping tag is to use Event Sequence Phase (page 103).

Master Traces (Volume 6, page 247) may also correspond to use cases but they should ideally correspond to only one use case instance.

²³ http://en.wikipedia.org/wiki/Use_case