Figure 7-12 Context diagram with blocks and ports
Requirements and understanding context
Requirements on the system at this level can be represented either as system attributes or as requirements that are related to the system and depicted on a requirements diagram. We do not want to try to represent all system requirements on a diagram or as attributes; that would produce a very complicated unreadable diagram because of the possibly large number of requirements. But if there is a small set of requirements that constrain the system in such a way that the architecture is likely to be influenced by them, it would be good to represent this visually.
For example, the range desired for a radar will influence its size and weight, due to power needs. Also, if we want to provide automated reasoning or simulation capabilities, we will want to include as much information as needed to drive our reasoning or simulation engines.
