An interface is a connection between two or more elements or solutions.
Interface analysis is used to identify where, what, why, when, how, and for whom information is traded between solution elements.
Most solutions need one or more interfaces to trade information with other solution elements, organizational units, or business processes.
There are different types of interfaces including:
- User interfaces: in this type of interface internal and external end users have to relate directly with the solution. Internal users are the organizational staff while external end users include auditors and industry regulators.
- Non-user interfaces: these include business processes, data interfaces between systems, application programming interfaces (APIs), and hardware devices.
Interface analysis are used to answer the following questions:
- Who would use the interface.
- What information is being exchanged through the interface.
- The amount of information being exchanged.
- When the information will be exchanged and how often it would be exchanged.
- Where the information exchange would happen.
- Why the interface is needed.
- How the interface should be implemented.
Interfaces should be identified earlier on in the initiative to allow the business analyst to provide the circumstances for gathering more detailed stakeholder requirements, and deciding on suitable functional analysis of the solution to meet the stakeholder needs.
Early identification of interfaces needs shows which stakeholders will gain from the different elements of the solution, help the business analyst decide which stakeholders should be available for other elicitation techniques.
Interface analysis has various components, which include:
1. Preparing for identification: The business analyst can support other techniques, such as document analysis, observation, scope modelling, and interviews, which can then be used to understand which interfaces need to be identified.
Context diagrams can be used to show high-level interfaces between human actors, organizational units, business processes, or other solution components.
The results of this analysis can be used to identify how often any existing interfaces are being used and any issues with them that may reinforce the need for change. The results may also help spot any important issues that need to be fixed in order for an interface solution to be developed.
2. Conduct interface identification: Business analysts recognize which interfaces are required in the future state for each connected system.
Some interfaces may be less obvious or less frequent such as an interfaces used for auditing, or for employee training.
For each interface, the business analyst has to:
- Define the function of the interface.
- Analyze the frequency of the interface usage.
- Assess which type of interface may be suitable.
- Extract initial specifics about the interface.
3. Define interfaces: Requirements for an interface are usually fixated on describing the inputs to and outputs from that interface, any validation rules that directed those inputs and outputs, and events that might activate interactions.
There may be a large number of possible interaction types, each of which needs to be identified. Interactions may be triggered by the typical or other flow of inputs and outputs in the business solution, or by unusual events such as failures.
Business analysts review who will use the interface, what information is passed over the interface, and when and where the interface takes place. The interface explains user workflow between systems, user roles and rights, and any administrative objectives for the interface.
Interface definition is dependent on guidelines, such as accessibility and workflow requirements. In order to identify any major design issues, interfaces between solution, process elements and people need a detailed analysis of the interface.
The interface definition includes the following:
• The name of the interface.
• The range of the interface.
• The interchange techniques between the two entities.
• The message layout.
• The exchange regularity.
Interface analysis has both its strengths and limitations, which include:
Strengths
• By stating the interface analysis early on, increased functional analysis is provided.
• A clear definition of the interfaces provides a structured means of assigning requirements, business rules, and restraints to the solution.
• Due to its wide application, it avoids over analysis of fine details.
Limitations
• It does not provide an insight into other features of the solution since the analysis does not analyze the internal components.