Each Cluster requires certain network resources. During Oracle Grid Infrastructure installation and configuration, you designate interfaces for use as public, private, or Oracle ASM interfaces. A cluster must have a public network access for clients and a private network for the cluster interconnect. Oracle recommends that you have at least two network interface cards. Oracle also supports the use of link aggregations, bonded, trunked, or teamed networks for improved bandwidth and high availability. For more information about the Network Interface requirements see Network Interface Hardware Minimum Requirements.
The storage network is only needed for network attached storage.