Description

A Message Start Event means that a message from a participant has arrived and triggered the start of a process.

A Message Start Event displays any of the following on a diagram:

• A Message Start Event name if the name is specified.
• A Message Ref property value if the name is unspecified.
• An Operation Ref property if the name and Message Ref are not specified.

Notation

• Interrupting Message Start Event
  
• Non-interrupting Message Start Event