Tag: Requirements

Logo OMG Systems Modeling Language (OMG SysML)

What’s new in SysML 1.5 – Requirements modeling

This post is the second part of the blog post series about the changes of SysML 1.5. The biggest novelty in SysML 1.5 is only visible on the second view. If you do not use the new feature, you will not recognize it. Since version 1.0 SysML provides the model element Requirement to model text-based requirements,…
Read more

SYSMOD Zigzag Base Architecture - FFDS example

The Base Architecture

How to relate requirements and architecture on different abstraction levels The SYSMOD zigzag pattern describes the different levels of abstractions and the relationship between requirements and architecture. Your system requirements do not start at the very top of the levels, i.e. they already include some technical decisions. The base architecture is the architecture one level above…
Read more

The SysML callout notation

I’ve just found this question in a sysml discussion forum: Is it really not possible to place requirements objects on an Activity, State Machine, or several other similar behavioral diagrams? Yes, it is not allowed to put requirement elements on a state machine or activity diagram. Since it is essential to show such cross cutting…
Read more

The SYSMOD Zigzag Pattern

Are your requirements really free of any solution? Requirements describe the What, the system architecture describes the How. Sounds easy, but…. Requirements are solution-free and they contain solution aspects at the same time. It depends on the level of abstraction. Let’s assume that you have absolutely solution-free requirements (I argue that those requirements are not…
Read more