Every feature in the line, device, and junction feature classes as well as every object in the domain network's junction object and edge object tables contains an Is connected attribute. This attribute helps identify isolated network features and objects by maintaining information about their connectivity to subnetwork controllers. When a feature is created, regardless of its connectivity, the Is connected attribute is set to unknown. This attribute is modified for network features depending on the operation being performed.
The Is connected attribute has the following values:
- Unknown—When a feature is created, the Is connected attribute is set to unknown, regardless of its connectivity to a source. Unknown is also set for features that are no longer part of a subnetwork; this is set when the subnetwork name is set to unknown for the features when executing the Update Subnetwork tool.
- True—If the feature has connectivity to a subnetwork controller, the Is connected attribute is set to true. This value is set by executing the Update Subnetwork or Update Is Connected tools.
- False—If a path doesn't exist and the feature is considered isolated, the Is connected attribute is set to false. This means that the feature does not have connectivity to any subnetwork controllers and is not part of a subnetwork. This value is set by executing the Update Is Connected tool. When no subnetwork controllers exist within a utility network, the Is connected attribute is set to false for all network features.
Review the following sections to understand what operations make changes to the Is connected attribute.
Modify a subnetwork controller
When a feature is set or removed as a subnetwork controller using the Modify Subnetwork Controller pane, the Is connected attribute is modified. The value is set to true when setting a feature as a subnetwork controller, and when removing as a subnetwork controller, the value is set to unknown. When the feature has terminals, this occurs when the last terminal on the feature is removed as a subnetwork controller. The Is connected attribute is modified when the changes to the subnetwork controller feature are applied in the Modify Subnetwork Controller pane.
Update Subnetwork tool
When a subnetwork is updated, the Is connected attribute is modified based on the connectivity of features to a subnetwork controller; this is based on the Tier or Subnetwork Name parameters specified in the Update Subnetwork geoprocessing tool.
Using the Update Subnetwork tool, the following edits are made to the Is connected attribute for subnetwork features:
- True—For features that are part of the subnetwork, the Is connected attribute is updated to true.
- Unknown—For features that are no longer part of the subnetwork, the Is connected attribute is updated to unknown when the subnetwork name is set to unknown.
The Update Subnetwork tool updates the Is connected attribute for subnetwork features. This process will not identify isolated features in the network that have no connectivity to the subnetwork controller or controllers. To identify isolated features, see the following section regarding the Update Is Connected tool.
Update Is Connected tool
The Update Is Connected geoprocessing tool modifies the Is connected attribute for all features in the entire utility network.
Using the Update Is Connected tool, the following edits are made to the Is connected attribute for features in a utility network:
- True—If a path exists from the feature to any subnetwork controller in the network, the Is connected attribute is set to true.
- False—If a path doesn't exist—in other words, the feature is disconnected from any subnetwork controller in the network—the Is connected attribute is set to false.
The date and time stamp for the Last Update Is Connected Time is listed on the Network Properties tab for the utility network in the General section.
See Identify isolated features for more information.