<From Wikipedia>
The Systems Modeling Language (SysML)[1] is a general-purpose modeling language for systems engineering applications. It supports the specification, analysis, design, verification and validation of a broad range of systems and systems-of-systems.
SysML was originally developed by an open source specification project, and includes an open source license for distribution and use.[2] SysML is defined as an extension of a subset of the Unified Modeling Language (UML) using UML’s profile mechanism. The language’s extensions were designed to support systems engineering activities.
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For the CAC, SysML is important because it is one of the key interoperability standards supported by Comet / CDP4. It can be used to exchange modeling information with a number of other tools such as Enterprise Architect, Cameo and others.