Wikipedia
In systems management, out-of-band management involves the use of management interfaces (or serial ports) for managing and networking equipment.
Out-of-band management allows the network operator to establish trust boundaries in accessing the management function to apply it to network resources. It also can be used to ensure management connectivity (including the ability to determine the status of any network component) independent of the status of other in-band network components.
In computing, one form of out-of-band …
Out-of-band management - Wikipedia, the free encyclopedia