There are two major categories of network virtualization commonly seen in cloud computing today:
. Virtual Local Area Networks (VLANs): VLANs leverage existing network technology implemented in most network hardware.
VLANs are extremely common in enterprise networks, even without Management Storage Service Management plane to nodes storage nodes (volumes) to compute nodes (instances) Internet to compute nodes Instances to instance Common networks underlying IaaS. They are designed for use in single-tenant networks (enterprise data centers) to separate different business units, functions, etc. (like guest networks). VLANs are not designed for cloud-scale virtualization or security and shouldn't be considered, on their own, an effective security control for isolating networks. They are also never a substitute for physical network segregation.
. Software Defined Networking(SDN): A more complete abstraction layer on top of networking hardware, SDNs decouple the network control plane from the data. This allows us to abstract networking from the traditional limitations of a LAN.
Ref: CSA Security Guidelines V.4 (reproduced here for the educational purpose)

The primary issue to remember when governing cloud computing is that an organization can never outsource responsibility for governance, even when using external providers. This is always true, cloud or not, but is useful to keep in mind when navigating cloud computing's concepts of shared responsibility models Ref: CSA Security Guidelines V4.0

The four layers of Logical Model for cloud computing according to Cloud Security Alliance are:
1. Infrastructure: The core components of a computing system: compute, network, and storage. The foundation that everything else is built on. The moving parts.
2. Metastructure: The protocols and mechanisms that provide the interface between the infrastructure layer and the other layers. The glue that ties the technologies and enables management and configuration.
3. Infostructure: The data and information. Content in a database, file storage, etc.
4. Applistructure: The applications deployed in the cloud and the underlying application services used to build them. For example, Platform as a Service features like message queues, artificial intelligence analysis, or notification services.

The primary tool of governance is the contract between a cloud provider and a cloud customer (this is true for public and private cloud). The contract is your only guarantee of any level of service or commitment Ref: CSA Security Guidance V4.0

Storing is the act committing the digital data to some sort of storage repository and typically occurs nearly simultaneously with creation.
Reference: CSA Security Guidelines V.4(reproduced here for the educational purpose)