Which Cisco ACI model implementation stage is an abstract expression that is derived by the APIC?
- the hardware model
- the resolved model
- the concrete model
- the logical model
Of the available choices, the Cisco Application Centric Infrastructure (ACI) model resolved model is an abstract expression that is derived by the Cisco Application Policy Infrastructure Controller (APIC). The resolved model is a stage that is derived by the APIC in abstract from the logical model stage. In other words, the logical model is converted to the resolved model by the APIC. This stage is a lower-level representation of the ACI model than the logical model stage in that it represents how configuration components are sent to the infrastructure when a policy is executed.
The logical model stage of the Cisco ACI model is not an abstract expression that is derived by the APIC. The logical model is typically configured by the user in the Cisco APIC. The application network profile, which is often simply referred to as the application profile, is an expression of the logical model. The application network profile is an object that acts as the container for all other objects in the model; it tiers endpoint groups (EPGs) and represents how they relate to each other.
The concrete model is not an abstract expression that is derived by the APIC. The concrete model is a stage that is derived from the resolved model in that it represents the ACI model after configuration has been delivered to each endpoint in the fabric. The concrete model is typically created when switches in the ACI model convert the resolved model. However, there are some objects in the logical model that do not require conversion to the resolved model to also be represented in the concrete model. These objects include physical port properties that are already local to a given leaf or port.
The hardware model is not an abstract expression that is derived by the APIC. The Cisco ACI model consists of only three implementation stages. The hardware model is not one of those stages. Instead, concrete objects are consumed by application-specific integrated circuits (ASICs) on hardware.