MLDesigner is an integrated modeling and simulation tool for the design and analysis of complex embedded and networked systems. MLDesigner speeds up modeling, simulation and analysis of discrete event, discrete time and continuous time systems concerning architecture, function and performance. The tools is based on ideas of the "Ptolemy Project", done at the University if California Berkeley. MLDesigner is developed by MLDesign Technologies Inc. Palo Alto, CA, USA in collaboration with Mission Level Design GmbH, Ilmenau, Germany. Concept System models are composed in a graphical editor. These hierarchically structured block diagrams are stored in MML (Model Markup Language), a dialect of XML. Models may therefore also be generated automatically by XML-transformations from other XML based models descriptions e.g. UML (via XML Model Interchance, XMI), BoNES, Cossap or OPD/OPM (Object Process Diagram/Modeling) models. Executable models (systems) are composed of modules and primitives, which are connected via typed in- and out-put ports and/or attributes (parameters, resources, memories, events). Modules can be composed of other modules and/or primitives. Primitives are the smallest units in MLDesigner models. The behaviour of primitives is either coded in ANSI C/C++ or modeled using Finite State Machines (FSM) and/or may exchange information with other simulators, internet based systems or hardware. All modules and primitives of a simulation model may be dynamically instantiated (dynamic instance support), enabling simulation with dynamically changing architectures and architectural optimization. MLDesigner comes with more than 2000 library elements. For system modeling therefore the development of new primitives is generally not required. Operation Simulations in MLDesigner are based on specific, matter depending models of computation (MOC), called domains. The type of domain determines how and in which order the exchange of data structures between the model elements is done. Included are discrete time synchronous (SDF) and dynamic (DDF) data flow, continuous time and discrete event domains. The MLDesigner kernel automatically synchronizes model elements created in different domains within a single system. Therefore MLDesigner supports the modeling and simulation of time discrete, time continuous and event discrete systems. Domains The Multi-Domain-Simulator MLDesigner supports among others the following domains: SDF-Domain (Synchronous Data Flow) The SDF domain is a data driven, statically scheduled domain in MLDesigner. It is used to model time discrete systems, as for example digital signal processing, general or special purpose processors. In this domain model elements exchange synchronously a fixed quantity of data elements, so called particles. "Statically scheduled" means that the firing order