Read the paper: W.M.P. van der Aalst, A.H.M. ter Hofstede, M. Weske, Business process manage-ment: A survey, in: Proceedings of BPM 2003, LNCS 2678, Springer-Verlag, 2003. link
The following figure is taken from this paper.
a) Assign the following software systems to the appropriate layer as depicted above. Is a clear assignment always possible? What is the relation of these software systems to business processes?
b) Give examples for the statement that the layers depicted above are moving to the outside while absorbing new functionality. Is there also a movement to the inside?