Which type of flow is represented by dotted lines in BPMN?

In Business Process Model and Notation (BPMN), dotted lines are used to represent message flows. This notation illustrates the communication between different participants or processes that are often separate but interact with each other. Message flows help clarify how information is exchanged in the context of processes rather than showing direct sequence or order of activities.

While sequence flows, depicted by solid arrows, indicate the order of activities within a single process, message flows are crucial for depicting interactions across different pools or lanes, which often represent distinct business entities. This distinction is vital for understanding how tasks are coordinated between different stakeholders or systems in a business process.

Recognizing the significance of message flows in BPMN allows for better modeling of inter-organizational processes, thereby enabling a clearer understanding of how different roles and systems communicate, which is critical for effective business process management.