What is the difference between interrupting escalation event and error event?

Question

As I understand escalation event is used to inform parent process. If escalation event is interrupting, it means that regular flow will be ignored and a new flow will be handled. But it is similar to error event. What is the difference?

Answer 1

You are right, escalation events are used to communicate from a subprocess to a parent process. Unlike an error, an escalation event is, by default, non critical and execution continues at the location of throwing.

Answer 2

The difference in notation is that

• Error events are always interrupting (as the name suggests), either as an Event Sub-process start event or a Boundary event of a Sub-process.
• Escalation events are by default non-interrupting but they can also be modelled as interrupting events. They can, just like Error events be Event Sub-process start events or Boundary events.

The more important semantic difference is that Escalation events gives you a bit more flexibility in modeling a business activity. Not everything that goes wrong during a process is an error. Sometimes, things just don't go quickly enough or there is a non-business critical piece of information that the parent process should know about.

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