Which of the following is NOT considered a structural domain?

In the context of utility networks, structural domains pertain to the physical and permanent elements that help define the structure of the network. Junctions, lines, and boundaries are all integral parts of this structural framework. Junctions represent points where different line segments meet, while lines are the conduits through which utility services flow, like water or electricity. Boundaries delineate the limits or extents of network features or areas.

Traffic control, on the other hand, is more aligned with operational or management aspects rather than structural characteristics. It typically involves systems or mechanisms designed to regulate the movement of traffic or manage the flow within the network but does not contribute to the fundamental physical structure of the utility network itself. Therefore, in identifying what is NOT considered a structural domain, traffic control is the correct choice, separating it from the core physical components of the network.