Welcome to the homepage of Yasper.

Yasper is a tool for modeling and simulating stepwise processes.

Yasper was designed to make it easy to model and simulate typical workflow processes.

Yasper uses extended Petri nets as its modeling technique. Petri nets describe a process by means of transitions (steps in the process) and places (conditions that hold before and after steps). It is precisely defined what execution can do, which makes analysis and simulation very useful.

Yasper supports manual simulation, in which the user selects execution steps by clicking in the model, and automatic simulation, which randomizes the choice of steps and produces an aggregated report with relevant statistics.

Yasper models directly support some popular Petri net extensions, and can emulate several other techniques, such as state machines, flowcharts, UML 1 activity diagrams, and EPCs.

Yasper does not represent a radical new technique for modeling or simulation. Colored Petri net tools (e.g. CPN Tools, ExSpecT, ReNeW) can do what Yasper does; Yasper just makes it easy.

Yasper was developed in collaboration between TU Eindhoven and Deloitte.

Introductory materials on Yasper are still limited:

• the manual distributed with Yasper has a chapter with modelling examples for each feature
• the slides of a presentation at ESM'2005, Porto illustrate the features with a single example with variations
• a short paper about Yasper (requires IEEE Digital Library subscription), published at ACSD'06, uses similar variations