Requirements Engineering

In my first column, I introduced the OPEN Process Framework (OPF), which provides an industry-standard terminology for organizing and communicating process engineering concepts. In it, I also introduced the reusable requirements engineering work products that are part of the OPF. This second article introduces the remaining reusable process components that are useful for requirements engineering: specifically, the requirements work units, the producers of the requirements work products that perform these work units, and the associated languages that are involved in requirements engineering. Requirements engineering is an activity, one of several kinds of work units that are performed on endeavors. As the following simplified figure illustrates, work units can be categorized (in order of decreasing scope) activities, tasks, and techniques, whereby: • An activity is the highest-level work unit consisting of a cohesive collection of one or more tasks that are performed by one or more collaborating producers when producing a set of one or more related work products or providing one or more related services. • A task is a mid-level work unit that models a functionally cohesive operation performed by one or more producers. • A technique is a low-level work unit that is the reified implementation of (i.e., way of performing) one or more tasks.