Question

Explain in-band, out-of-band and combination management.

Answer 1

In-band management refers to the management of network itself, using a Telnet/SSH connection to a router or by using SNMP-based tools. In-band is the common way to manage the network, where actual data/ production and management traffic may use the same path for communicating with various elements. For large or business-critical networks, in-band network management is not enough. If the network is down, reachability to network device is affected and this is a big risk for the organization and its business. We need an alternate path to solve the problem or to access the source of the problem.

The primary benefit of an out-of-band management interface is its availability when the network is down, a device is turned off, in sleep mode, hibernating, or otherwise inaccessible. OOBM can be used to remotely reboot devices that have crashed and manage powered-down devices.  When network is down and traffic is not flowing, in such a scenario, an alternate path is required to reach the network nodes. Here we need a secure remote emergency network access path to manage and troubleshoot the device when network traffic is down. For critical networks, in-band management tools are not enough. Management using independent dedicated channels is called out-of-band management.

Combination management is the method of combining in-band and out-of-band management in a single solution, which enables business to significantly increase the availability, quality and security of the services you deliver.