Which of the following best describes an endpoint registry?
- a collection of current endpoints known to the Cisco ACI
- a controller for distributing, tracking, and updating policies
- a collection of rules applied to endpoints, existing or hypothetical
- a collection of endpoints to which policies are distributed
Of the available choices, an endpoint registry can best be described as a collection of endpoints already known to the Cisco Application Centric Infrastructure (ACI). The endpoint registry is the second of two logically coupled components of an endpoint policy: it stores the operational state of each endpoint. In Cisco ACI, the endpoint registry is stored in a distributed database within the ACI fabric. Endpoint policies are used to define how endpoint groups (EPGs) communicate with each other.
A policy repository can be best described as a collection of rules applied to endpoints, existing or hypothetical. A policy repository is the first of two logically coupled components of an endpoint policy; it is typically centralized in the Cisco Application Policy Infrastructure Controller (APIC) or in leaf nodes in the ACI fabric. The policy repository component of an endpoint policy stores rules that can be applied to existing endpoints, planned endpoints, or deleted endpoints.
An EPG is a collection of endpoints with identical requirements; it is a primary element of a tenant. EPGs are logical groupings of endpoints that provide the same application or components of an application. For example, a collection of Hypertext Transfer Protocol Secure (HTTPS) servers could be logically grouped into EPG labeled WEB. EPGs are typically collected within application profiles. EPGs can communicate with other EPGs by using contracts.
The Cisco APIC is a controller for distributing, tracking, and updating policies. In other words, it is a central component of a Cisco ACI fabric that is used for both automation and management.