I want a diagram to represent the architecture of my system (height-level).
The architecture is very simple, so the diagram should be very simple too.
The system is kind of ERP. I have a Business Process, which executed by BPEL engine. In additional there is esb-engine which responsible to run esb components. The BPEL-engine and the esb-engine run on application server.
If you wanted to get really fancy you could possibly use a UML deployment diagram to represent this. You can draw this in Visio, in Powerpoint (which I use because usually you're going to present it anyway) or in any of a number of good free UML tools like ArgoUML.
Who is the audience of the diagram? What will they use the diagram for? Before you have answered those questions, it's impossible to say what should be communicated, let alone how.
The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - Heraclitus