Management and the API network

In a smaller deployment, the traffic for management and communication between the OpenStack components can be on the same physical link. This physical network provides a path for communication between the various OpenStack components such as REST API access and DB traffic, as well as for managing the OpenStack nodes.
For a production environment, the network can be further subpided to provide better isolation of traffic and contain the load on the inpidual networks.

The Storage network

The storage network provides physical connectivity and isolation for storage-related traffic between the VMs and the storage servers. As the traffic load for the storage network is quite high, it is a good idea to isolate the storage network load from the management and tenant traffic.