HOPEX IT Architecture V2 > Architecture Specification > Modeling application architectures > Describing the structure and services of an application > Describing an IT Service with HOPEX IT Architecture
Describing an IT Service with HOPEX IT Architecture
*An IT service is a software component of an application, that can't be deployed alone and that realizes a sub-set of the functionalities of this application either for end users of this application or inside the application (or another application). This includes batch programs.
IT Service diagrams 
An application service is described by several types of diagrams:
• an application system structure diagram, is used to represent the interactions between the application service components in exchange contracts formalism.
*For more details, see Using IT Service Structure Diagram.
• a scenario of IT Service Flows presents the application flows exchanged between the described IT service and partners : IT services or micro-services used . A scenario can represent a particular use case of the IT service or more globally all the flows exchanged within this IT service.
• a scenario of sequences of flows presents the agents necessary for the scenario (IT services, micro-services, data stores) and sequence application flows exchanged with IT services.
Accessing the list of IT services 
To access the list of IT services using the Inventories navigation pane:
*Select Software > IT Services.
The list of IT services appears in the edit area.
IT Service properties 
The complete description of an IT Service is accessed from its properties pages.
The Characteristics properties page for an IT Service provides access to:
• its Owner, by default during creation of the IT service, the current library.
• its Name,
• the Type,
• the Visibility,
• the Review Status,
• the text of its Description.
• The Functional scope section is used to describe:
• The business capabilities covered by the IT Service,
*.A business capability is a set of features that can be made available by a system (an enterprise or an automated system).
*For more details on business capabilities, see Describing Business Capabilities with HOPEX IT Architecture.
• The Implemented Functionalities that are fulfilled by the IT service.
*A functionality is a service required to perform a work. This functionality is generally necessary within an activity in order to execute a specific operation. If it is a software functionality, it can be provided by an application.
*For more details on functionalities, see Describing a Functionality Map with HOPEX IT Architecture.
*For more details on fulfillments, see Using fulfillment mechanisms.
• the Use Cases section, see Creating an application Use Case Diagram.
• The Responsibility section relates the person(s) responsible for the IT service
• Software Designer
• Local Application Owner
• IT Owner
*For more details on these roles, see Business Roles of HOPEX IT Architecture..
• the Technologies section provides access to the list of Software Technologies used by the IT Service.
*A technology is a definition or format that has been approved by a standards organization, or is accepted as a standard by the industry.
*For more details on software technologies, see Describing a Software Technology.
• the Risks section presents the risks associated with the application, see Specifying the Risks Associated with an Application.
With HOPEX IT Architecture an IT service is described by other property pages. See HOPEX IT Architecture properties pages content.
Using IT Service Structure Diagram 
*For more details on use of a structure diagram, see Application structure diagram
With HOPEX IT Architecture, the components of an IT Service can be described by an IT Service structure diagram.
An IT Service Structure Diagram includes:
• IT services,
• micro services,
• Physical data stores; see Managing Data.
• access, request and service points; Creating a Service Point or a Request Point.
• interactions between the components
*An interaction represents a contract established in a specific context between autonomous entities that are internal or external to an enterprise. These entities can be enterprise org-units, applications, activities or processes, as well as external org-units. The content of this contract is described by an exchange contract.