Monitoring and management: network observability, capacity, logging

You cannot protect a network you cannot see. Monitoring and management is the discipline of continuously collecting data about what the network is doing, deciding whether that behavior is normal, and keeping the infrastructure healthy enough to deliver the availability the business needs. For the CISSP this topic sits where security meets operations: the same telemetry that tells a network team a link is saturated also tells a security team that a host is sending data out at 3 a.m.