Esri Utility Network (Junction and edge objects)

Junction and edge objects are nonspatial network objects used to model and work with a large number of real-world features that share a common geographical space.

for example,

• the strands inside of a fiber cable.
• conductors in an underground duct.

This allows organizations to model their network in more detail without the need to create features with shapes for every asset.

They support connectivity with other features and can act as a container (such as a switch box that contains multiple ports).

Associations are used to model connectivity, containment, and structural attachment between junction objects, edge objects, and other features in the network.

The structure and domain networks include two additional tables to model nonspatial objects.

Domain network:

• EdgeObject.
• JunctionObject.

Structure network:

• StructureEdgeObject.
• StructureJunctionObject.

One of the primary capabilities that expose the power of the utility network is the ability to model assets as they appear on the ground with a high degree of realism.

Rows in both the JunctionObject and EdgeObject attribute tables participate in the network topology in the same way as spatial features to enable analytic capabilities such as tracing and diagrams.

Asset modeling is not limited to simple representation of devices, cables, pipes, and so on; it also includes how they can be used for analysis.

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Only the highest-level asset in the hierarchy must be represented as a feature with a shape, while all the other assets can be represented in a tabular format as either a junction or edge object associated with the spatial feature.

example: Telecom cables and the individual strands of fiber that exist in each cable. Telecom cables can contain thousands of fiber strands that transport data through the network. With assets such as these, it is necessary to model each individual strand, since each customer service may only use one or two. These nonspatial objects allow additional levels of granularity to be modeled effectively in this scenario. Representing thousands of fiber strands as spatial features could prove to be problematic, as you would have to work with stacked geometry, which would negate the value of spatial representation. cable could be modeled as a line feature and serve as a container for the fiber strand content represented as edge objects. The line feature is used to display a spatial location for the fiber strands to the user.

Associations with spatial features are used to determine the location of, and visually represent, nonspatial objects on a map.

example: A ?port modeled as a nonspatial junction object can be associated with a switch device as content in a containment association.

The locatability of nonspatial objects is important because spatial features provide a mechanism to create dirty areas and validate edits made to nonspatial objects so they can be updated in the network topology.

Junction and edge objects are locatable when they are contained by or structurally attached to a feature within their containment or attachment hierarchy.

junction-junction connectivity associations cannot be used to determine the locatability of a junction object or edge object.

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An edge object may also be located when associated with a junction at its endpoints or in situations where the edge object is associated with a locatable junction object through a junction-edge or junction-edge midspan connectivity association.

• In scenario 1, edge object D is locatable through a junction-edge connectivity association with the point feature C.
• In scenario 2, edge object G is locatable through a junction-edge connectivity association with junction object F, which is locatable through containment association 1 with point feature A.
• In scenario 3, edge object K is locatable through a junction-edge midspan connectivity association with junction object H, which is locatable through containment association 2 with point feature C.

When unlocatable objects are discovered, the tools return an error that includes the class name and global ID of the objects for inspection.