jgb@ektools.kodak.com (Joanne Green-Blose) (05/01/91)
I have a question for anyone knowledgeable in SA/SD who may have used the event paritioning approach. Yourdon discusses this method in his book Modern Structured Analysis. Basically you begin with "events" to your system which are generated by external terminators. The collection of all the events to the system makes up the Environmental Model. My problem is the implementation of this phase. My group is attempting to try this. We divied up the terminators in our context diagram among us and gave each individual the action item to find events for their respective terminators. Then we review the events as a group. We review them mainly on legitimacy (is this an external event generated outside the system for ex.) and also to add/subtract other events. The problems we are having are many but one of them is in the granularity of the events. We can't seem to be consistent on how granular to get. For example, a lot of our system is very data-intensive and do we describe the event as for ex., "host computer downloads data" or do we break it down further like,"host computer downloads xyz data and also downloads abc data" etc. Does it make any difference? Does it make any difference if some of us have generic events while others are detailed? Also, is it possible to have event lists for some of the terminators but not for all? Would this throw a wrench in the system when you start attempting to draw DFDs? Any input from anyone who has some experience with this (now quite common) structured methodolgy would be most welcome! -Joanne Greene-Blose, Eastman Kodak Co.