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Utility network vocabulary

Essential utility network terms are listed along with their descriptions.


Analytics is the process of analyzing the utility network data to perform inspections of the network (utility network traces) and schematically represent the whole or parts of the utility network (network diagrams).

Asset group

The asset group of a feature defines its broad classification. The ASSETGROUP field for each network feature class is defined as the subtype field. Further classification of features is added by assigning attribute domains at the subtype level on the ASSETTYPE field.


A transformer is one of the subtypes for an asset group of an electric device network feature class.

Asset type

The asset type attribute of a feature defines a finer classification for each asset group in a network layer. The ASSETTYPE field in a network layer is a text field linked to an attribute domain of values. These attribute domains are assigned on the ASSETTYPE field at the subtype level for each network feature class. The ASSETGROUP field is defined as the subtype field for each network feature class. This allows a rich classification of network features using the asset group as a major classification and asset type as a minor classification of features.


A power transformer is an asset type of a transformer in an electric device network feature class.


Associations are created to associate features with one another. There are three types of associations: connectivity associations, structural attachment associations, and containment associations.


A connectivity association specifies that a transformer is connected to a fuse.

A structural attachment association specifies that a capacitor is attached to a pole.

A containment association specifies that a vault can contain valves and pipes.

Association rules

Association rules prevent an editor from adding logically invalid feature associations in a network. Association rules define the valid ways network features can be associated with each other. There are three broad types of association rules: connectivity rules enforce the types of features that can be connected, structural attachment rules enforce the types of devices that can be connected to a structure, and containment rules enforce the types of network features that can be contained in network container features.


Connectivity rule: A transformer can connect to a fuse.

Structural attachment rule: A capacitor can be attached to a pole.

Containment rule: A vault can contain valves and pipes.


Network features in a utility network can be connected to each other in two basic ways: either with a shared endpoint, vertex, or point (common x-, y-, and z-values) or with a defined connectivity association between two features that are not spatially coincident. This is called connectivity.

Learn more about connectivity and traversability


A pump placed at the end of a water pipe will have connectivity established because of the shared location.

Connectivity association

One of the three types of network associations. A connectivity association allows the individual features to be represented in the network and establishes a connection between the network features that are spatially disjointed. This is an integral part of performing tracing and analysis.


A connection between a switch and a line is an example of connectivity association. A connection between a fuse and an arrester that are not spatially coincident is another example of a connectivity association.


A container represents an assembly of network features that are normally shown as a single feature on a map. For example, an electrical switchgear container feature contains internal switches, fuses, and a busbar, which are important for tracing analysis, but a map showing all these internal features would be too dense. Network features inside a container can be connected to features outside a container.


Electrical substations and pumping stations are examples of container features.

Containment edit mode

Containment edit mode is enabled using the Enter Containment command in the Associations group on the Data tab on the Utility Network tab. In this mode, created features that have a supporting rule are automatically added to the active container as content. Editing in containment edit mode shows what network features are inside the active container and how they are connected. Analysis results are also shown inside the container view.


While editing an assembly of features, you will usually enter containment edit mode. New features that are created are automatically added as content for the assembly.

Containment associations

One of the three types of network associations. A containment association is the relationship between a container feature and a contained network feature. Containment associations allow you to create a detailed model of all significant devices and reduce map clutter in dense areas with the use of the Display content command. Valid containment associations are enforced through containment rules.


The relationships between an electrical vault and all the devices and lines it contains are examples of containment associations.

Database utility network owner

The concept of data ownership for a utility network is influenced by its service-based architecture. There are two owners for a utility network dataset: the database owner and the portal owner.

The database user that is the data owner for the utility network serves as the database utility network owner. This is determined by the database user used in the data source when a utility network is created. The utility network must be accessed as the database utility network owner for configuration and publishing tasks.

Diagram view

The diagram view shows a schematic view of your network. A diagram is a symbolic representation of features in a utility network with an applied visualization technique. Diagrams can also show the results of a tracing analysis.


At an electric utility, one type of diagram view is called a one-line diagram.


Defines how resources flow through terminals on a device feature. All terminal configurations require directionality to be defined as directional or bidirectional. A directional terminal configuration indicates that the network commodity can travel only one way through a device. A bidirectional terminal configuration indicates that the network commodity can travel in either direction through the device; there are no distinct upstream or downstream terminals.

See Terminal management for more information.

Dirty areas

Dirty areas mark modified features in a map that are out of date in the network topology. Dirty areas are used as visual cues to show the areas that must be validated to maintain the network topology. Dirty areas are cleared when the network topology is validated.


A new medium-voltage line is constructed in the map, and a new dirty area is created that is visible around this feature.

Disjoint subnetwork

If subnetwork controllers that share the same subnetwork name cannot be traversed to one another, the subnetwork is considered disjoint. For tiers within a partitioned domain network the Set Subnetwork Definition geoprocessing tool includes an option to Support Disjoint Subnetworks. The default is to not support disjoint subnetworks for partitioned domain networks. Tiers in a hierarchical domain network always have this option to support disjoint subnetworks set as true. This property of the tier can be viewed using the Network Properties tab of the utility network layer properties.

Domain network

When you create a utility network, you will add one or more domain networks to the utility network. A domain network is an industry-specific collection of feature classes such as electric distribution or gas transmission. Sometimes a utility network will have two domain networks at the transmission level and distribution level. A utility network can also have crossing domain networks, such as gas and water, if they are both managed by that utility.


An electric, gas, or water utility may have two domain networks for modeling the delivery of their resource: transmission and distribution.

Geometric coincidence

When two or more features exist in the same x-, y-, and z-location, they are geometrically coincident.


Sometimes features can occupy the same x- and y-locations, such as devices stacked on a pole. Assigning z-values features at the same x- and y-locations will help ensure features are not geometrically coincident.

Inconsistent subnetwork

When a subnetwork has multiple subnetwork controllers and the Subnetwork Name attribute is not consistent, the subnetwork is considered inconsistent. For example, in a subnetwork with five subnetwork controllers, four of the subnetwork controllers have the correct subnetwork name, while the fifth has a different name.

If inconsistent subnetworks are discovered during the update process, an error is returned in the Update Subnetwork tool and point error features are generated for the subnetwork controllers. Inconsistent subnetworks are also reported when performing a subnetwork trace.

Learn more about updating subnetworks.

Junction-edge connectivity rule

A junction-edge connectivity rule is a type of connectivity rule that governs which junction network features can be connected to endpoints or vertices of line network features.


A switch can be connected to the endpoint of a medium-voltage line.

Junction-junction connectivity rule

A junction-junction connectivity rule is a type of connectivity rule that governs the junction network features that can be connected to other junction network features. Applying this rule allows a connectivity association to be defined between two disjointed junction network features.


A capacitor can be connected to a switch.

Map view

The map view shows a cartographic display of your utility network. When edits are performed, dirty areas will appear on the map showing where the network topology is not current.

Midspan connectivity

When connecting network features to a line, you can make connections at either the endpoints or the midspan vertices of a line. Using the midspan vertices of a line allows you to create network features without breaking network lines where the physical line is continuous.


A typical location for midspan connectivity is where a service drop connects to an electric distribution line. Subnetwork taps also occur midspan of line features.

Network attribute

Network attributes are associated with attributes on features in your network. They are derived from feature attributes and cached inside the network topology to aid in performance as feature attributes are evaluated during a trace or while performing subnetwork management tasks. The values stored as attributes for features in a map are reflected or updated in the associated network attribute each time you validate the network topology.


Electric phases can be modeled as a network attribute so that a trace can be run on only one of three electric phases.

Pipe diameters can be defined as a network attribute to constrain gas and water traces.

Network categories

A network category is a tag used to represent a characteristic of an asset in your network. created and assigned to network feature classes for specific asset group and asset type combinations.

See Network categories for more information.


A network category of Protective can be used to limit traces of electric network features to devices or equipment that is used to protect the system, like fuses or reclosers.

Network diagrams

Network diagrams provide a simplified view of a network, which is useful for different types of engineering analysis. These are also called schematic representations and apply user-specified algorithms to collapse nonessential features and highlight crucial features for an engineer's view of the network.


A one-line diagram for electric utilities is a network diagram.

Network topology

The network topology enables tracing analysis and rapid retrieval of network features. When edits occur on a utility network, affected parts of the network topology are displayed as dirty areas to indicate that the network topology does not match the edited features. The network topology stores all types of associations—connectivity, containment, and structural attachment—in the utility network. A validate network topology operation will update the associations in the area where edits took place and produce accurate tracing results.

To learn more, see Network topology.

Portal utility network owner

The concept of data ownership for a utility network is influenced by its service-based architecture. There are two owners for a utility network dataset: the database owner and the portal owner.

The active portal user when the utility network is created serves as the portal dataset owner. The portal utility network owner must meet certain requirements and prerequisites. Having the portal utility network owner signed in is a prerequisite for certain network configuration tasks as well as for publishing utility network layers. Tools that require an active portal connection with the portal utility network owner list this in the usage notes.

When accessed from a database connection established as the database utility network owner, the Portal Utility Network Owner is listed in the General section of the Network Properties dialog box.

Learn more about updating the portal utility network owner

Preset template

A preset template allows an editor to quickly place a complex collection of features. Preset templates create all types of needed associations as well as place network features. Preset templates are part of the core ArcGIS Pro editing framework and work with the association framework in the utility network.


A preset template would place a switchgear container with all its internal switches, fuses, and busbars and connect them properly.

Service territory

The service territory is an m- and z-enabled polygon feature class containing one or more features. This is used as input when creating a utility network. The extent of the features in the service territory feature class are used to define the network extent. The network extent is a single polygon feature that is calculated by aggregating the spatial extents of all input features; it is created slightly larger than the aggregated extent from the input service territory features. The polygon that encompasses the network extent can be viewed by displaying the dirty area for a utility network when the network topology is disabled.

The network extent represents the area in which the network topology is maintained. This also restricts the editable area for all of the structure network and domain network features collectively. To restrict the creation of network features at a finer level, a constraint attribute rule can be created using Arcade geometry functions such as Intersects as part of the script expression.


A service territory spans the operational area of a utility. It can be roughly the area of a city, state, or province.

Structural attachment association

One of the three types of network associations. A structural attachment association is the relationship between a network feature and a structure feature. Structural attachments are stored in the network topology for rapid identification of devices that are mounted on a structure.


A transformer bank has a structural attachment with the pole or pad on which it is mounted. The transformer bank represents the attachment, and the pole or pad serves as the structure in the association.

Structure network

Every utility network has a structure network that represents the features that support the devices and lines that convey a resource. All domain networks in a utility network share a common structure network.


An electric network has poles, pads, cabinets, and other structural features that are utility assets but do not directly carry the delivered resource.


A subnetwork represents a topological subpart within a tier where all the connected features are defined by the same subnetwork controller or controllers. To create a subnetwork, a subnetwork controller is set, the network topology is validated, and the subnetwork is updated.

To learn more, see Subnetworks.


Subnetworks are called circuits in electric systems and pressure zones in gas and water systems.

Subnetwork-based trace

There are many core trace types provided with the Trace geoprocessing tool. Subnetwork-based traces rely on information from the subnetwork trace configuration. This is part of the subnetwork definition for a tier and is used to limit the scope of the trace results when specifying the Domain Network and Tier parameters in the Trace tool.

Subnetwork-based traces that use the subnetwork definition in the trace configuration:

Learn more about utility network trace types

Subnetwork controller

A subnetwork controller is a type of network feature from which a resource is delivered or collected. A subnetwork controller type is defined for each domain network and when the tier is configured it is defined to use one or more of the controllers in the domain network. Certain asset group and asset type features in the device feature class are configured to allow features to be set as subnetwork controllers; this done by assigning a network category. Subnetwork controllers are set for device features using a specific terminal and are used as start or end points for tracing analysis.

Learn more about subnetwork controllers


For an electric system, a subnetwork controller for electricity is a power generating station or substation. For a gravity-fed system, a subnetwork controller can be a reservoir for a water delivery system.

System junction

A system junction is a hidden network feature that is placed at the endpoint of a network edge element when there is no user-defined junction. System junctions are generated during the initial enabling of the network topology or through validating the network topology. These features are hidden in the map view, but can be displayed in a network diagram view.

There are a few situations in which system junctions are created:

  • A single edge element with no user-defined junctions at the endpoints.
  • Two edge elements that share an endpoint and do not have a user-defined junction connecting them.
    • If the edge features have the same Asset group and Asset Type attributes, a system junction is created between the edge features and connectivity is established.
    • If the edge features have different Asset group and Asset Type attributes, a system junction is created at the end of each edge feature, and connectivity is not established. Error features are created.
Learn more about feature restrictions


Terminals model physical connections on a device. While not all devices require terminals, there are cases where terminals are necessary. Devices require terminals that will serve as subnetwork controllers when there are three or more connections to a device. The use of terminals allows a more realistic modeling of some devices and enables more accurate data exchange to external analytic systems.

See Terminal management and Device terminals for more information.


A transformer has high- and low-side terminals. A circuit breaker has source-side and load-side terminals.

Terminal configuration

A terminal configuration defines how a resource can flow within a device type that has defined terminals. When you create a terminal configuration, you define whether the resource can flow in both directions or only one direction, the name of terminals, whether a terminal is on the upstream or downstream side of the device, which paths between terminals are valid, and the default path through terminals. Once created, a terminal configuration is assigned to an asset type of an asset group in a device feature class.


A delta-wye transformer will have a terminal configuration that specifies the valid pathways between the high-side and low-side terminals.


Tiers are used to segregate and manage the final architectural piece of a network: subnetworks. A single tier defines a collection of individual subnetworks that all share the same properties and adhere to the same restrictions. Properties are defined when you add a domain network and create tiers for the utility network. These properties determine the layout of tiers and their position relative to the rest of the tiers in a domain network.

For more information, see Network hierarchies with tiers and Tiers.


An electric distribution domain network can be modeled with two tiers, where the medium-voltage tier starts at the load-side terminal of the outbound circuit breaker of the substation. The circuit breaker converts transmission-level voltages to medium-level voltages and traverses all the lines and devices until it reaches the high-side terminal of distribution transformers, which convert electric power to low voltages.

Trace analysis

Common types of analysis done with a network involve traces. A utility may want to know every network feature that is connected to a source, find loops in a network, or find all features upstream or downstream from a selected point. Some types of traces are constrained by specific devices, such as protective devices, and the definitions of those device types are specified by device categories in a domain network.


Examples of trace analysis are upstream traces, downstream traces, and connected traces.


Two related concepts in the utility network are connectivity and traversability. Connectivity describes the potential range of the resource flow (electricity, water, gas, or other). Traversability describes the actual range of resource flow according to the current state of devices that can impede flow, such as valves or switches. The definition of subnetworks that are delimited by the present status of interrupting devices (switches and valves) illustrates the concept of traversability.

Learn more about connectivity and traversability


A water system can have many connected pipes, but closed valves disconnect zones of water delivery from one another. Both point and line features can be disabled, limiting the flow of a resource.

Utility network

A utility network is a collection of domain networks (gas, water, electric, or other) plus a structure network. An organization will specify the set of domain networks that it manages when it configures a utility network. It is possible to define associations across domain networks and enable tracing analysis across those domains. For example, you can perform electric tracing analysis from transmission to distribution levels with a utility network with electric transmission and electric distribution domain networks. A utility network also has a service territory to constrain the valid geographic placement of features.


Each utility generally works with one utility network. This enables the utility to define associations from common structures. For example, a municipal utility might manage poles that carry cable TV and electrical power.