ID.AM-03:

Representations of the organization's authorized network communication and internal and external network data flows are maintained

Implementation Examples

Ex1: 

Maintain baselines of communication and data flows within the organization's wired and wireless networks

Ex2: 

Maintain baselines of communication and data flows between the organization and third parties

Ex3: 

Maintain baselines of communication and data flows for the organization's infrastructure-as-a-service (IaaS) usage

Ex4: 

Maintain documentation of expected network ports, protocols, and services that are typically used among authorized systems