Network Diagram Cycle in Project Management – Definition and Meaning

A network diagram cycle refers to a potential error or undesired situation in a network diagram (a graphical representation of project workflows and dependencies), in which a chain of links (dependencies) results in an activity being dependent on itself, either directly or indirectly through a sequence of other activities. Such a cycle is a logical contradiction and prevents correct calculation of project duration and dates using standard network diagram techniques. Network diagram cycles must therefore be identified and resolved during project planning.

Example, best practice, and further information on the term

A simple network diagram cycle could occur if it is mistakenly defined that task A must occur before task B, task B before task C, and task C before task A. This is logically impossible. Project management software typically detects such cycles during network calculation and issues an error message. A proven best practice is to proceed carefully when defining links and to check the network logic to avoid cycles. This is part of schedule creation and optimization according to PMBOK and ensures logical dependencies in agile planning processes. Resolving cycles is necessary to achieve a calculable and realistic schedule.