The Cisco ACI App Center allows you to fully enable the capabilities of the APIC by writing applications running on the controller. Using the Cisco ACI App Center, customers, developers, and partners will be able to build applications to simplify, enhance, and visualize their use cases. These applications are hosted and shared at the Cisco ACI App Center and installed in the APIC.

APIC supports two types of applications:

• Stateful

• Stateless

A stateless application (app) is a simple HTML, CSS, or JavaScript based front-end that is run as part of the APIC UI. These apps are also referred to as front-end only applications. They can be launched from the Apps tab in the APIC UI or can be inserted as a separate tab in any part of the APIC UI.

Stateless apps are inserted in the APIC UI as an IFRAME. In this type of applications, app specific state is stored on the APIC for that app. The app queries APIC using its northbound REST APIs and retrieves information from the APIC. In stateless app, no state is maintained in the between two invocations of the app.

Some of the common examples for stateless app include the following:

• Data visualization apps that gather data available from querying the APIC and that can present them in a visual format.

• L4-L7 vendor specific configuration apps.

A stateful application (app) has a backend service that runs continuously on the APIC. Consequently, the app may store a state in this backend for specific functions. Stateful app’s backend service is run on APIC in a sandboxed containerized environment; namely a docker container. The service makes queries to the APIC using the APIC’s REST API interface. A stateful app may also have a front-end component in addition to backend component. This front-end component is inserted in the APIC UI as an IFRAME, in the same way as a stateless app. If a stateful app is developed without a front-end, then it is installed using REST APIs.

Some of the common examples for stateful app include the following:

• Visualization Apps that can plot graphs for the historical data for a specific time interval.

• Alerts apps that can send alerts based on certain events that are not supported natively in APIC.

• Monitoring apps that can track APIC’s events, faults, and statistics and analyze it for detecting anomalies.

• Apps to sync the data between APIC and a third party vendor.