OM-IND-0023: Application Instance Count (Indicator)

ID	OM-IND-0023
Formal Name	Application Instance Count
In-text Name	number of application instances
Version	`1.2`
Type	Base Indicator
Scale	Ratio Scale
Status	Recommended

Definition

Number of application instances within the scope of responsibility of the entity.

Components

Application Instance	cf. https://open-measure.atlassian.net/wiki/spaces/DIC/pages/834044036.
Entity	The organization or organizational unit for whom performance is being measured.
Scope of responsibility	An item is within the scope of responsibility of an entity when that entity owns the item, or has been delegated responsibilities in relation with the item.

Rationale

Knowing the number of application instances within an entity’s scope of responsibility is of critical importance to assure that this responsibility is fulfilled, whatever the responsibility is.

Limitations and Complexities

By definition, applications whose existence is not known cannot be accounted for. This limitation may constitute a risk in environments where data quality in inventories is not reliable.

In a complex environment with multiple entities having shared responsibilities across application instances (e.g. complex out-sourcing setups), responsibility scopes may be difficult to clarify.

Data Sources

Cloud Services Inventories
CMDBs
IT Applications Inventories
Third Parties Inventories

Formula

Let X be the set of known application instances.

Let e be the entity.

Let R be a set of responsibilities assigned to e.

Let s(X, e, R) = Y be defined as the function that returns Y, a subset of X where for each application instance y in Y, the entity e has at least some responsibility in R.

The formula for the indicator is then: i = |s(X, e, R)|

Indicators