ExplanationOracle Cloud Infrastructure File Storage service provides a durable, scalable, secure, enterprise-grade network file system. You can connect to a File Storage service file system from any bare metal, virtual machine, or container instance in your Virtual Cloud Network (VCN). You can also access a file system from outside the VCN using Oracle Cloud Infrastructure FastConnect and Internet Protocol security (IPSec) virtual private network (VPN).
Large Compute clusters of thousands of instances can use the File Storage service for high-performance shared storage. Storage provisioning is fully managed and automatic as your use scales from a single byte to exabytes without upfront provisioning.
The File Storage service supports the Network File System version 3.0 (NFSv3) protocol. The service supports the Network Lock Manager (NLM) protocol for file locking functionality.
Oracle Cloud Infrastructure File Storage employs 5-way replicated storage, located in different fault domains, to provide redundancy for resilient data protection. Data is protected with erasure encoding.
The File Storage service uses the "eventual overwrite" method of data eradication. Files are created in the file system with a unique encryption key. When you delete a single file, its associated encryption key is eradicated, making the file inaccessible. When you delete an entire file system, the file system is marked as inaccessible.
The service systematically traverses deleted files and file systems, frees all the used space, and eradicates all residual files.
Use the File Storage service when your application or workload includes big data and analytics, media processing, or content management, and you require Portable Operating System Interface (POSIX)-compliant file system access semantics and concurrently accessible storage. The File Storage service is designed to meet the needs of applications and users that need an enterprise file system across a wide range of use cases, including the following:

Explanation
Oracle Cloud Infrastructure File Storage service provides a durable, scalable, secure, enterprise-grade network file system. You can connect to a File Storage service file system from any bare metal, virtual machine, or container instance in your Virtual Cloud Network (VCN). You can also access a file system from outside the VCN using Oracle Cloud Infrastructure FastConnect and Internet Protocol security (IPSec) virtual private network (VPN).
Large Compute clusters of thousands of instances can use the File Storage service for high-performance shared storage. Storage provisioning is fully managed and automatic as your use scales from a single byte to exabytes without upfront provisioning.

Explanation
NVMe stands for non-volatile memory express. It is a storage protocol created to fasten the transfer of data between enterprise and client systems and solid-state drives (SSDs) over a computer's high-speed Peripheral Component Interconnect Express bus. The characteristics are:
1) Local NVMe is NVMe SSD-based temporary storage.
2) It is the locally-attached NVMe devices to the OCI compute instance
3) It is used very high storage performance requirements, lots of throughput, lots of IOPS, local storage and when you don't want to go out on network
4) Oracle does not protect in any way through RAID, or snapshots, or backup out of the box and data is not encrypted at rest.

Explanation
Oracle's mission is to build cloud infrastructure and platform services for your business to have effective and manageable security to run your mission-critical workloads and store your data with confidence.
Oracle Cloud Infrastructure offers best-in-class security technology and operational processes to secure its enterprise cloud services. However, for you to securely run your workloads in Oracle Cloud Infrastructure, you must be aware of your security and compliance responsibilities. By design, Oracle provides security of cloud infrastructure and operations (cloud operator access controls, infrastructure security patching, and so on), and you are responsible for securely configuring your cloud resources. Security in the cloud is a shared responsibility between you and Oracle.
In a shared, multi-tenant compute environment, Oracle is responsible for the security of the underlying cloud infrastructure (such as data-center facilities, and hardware and software systems) and you are responsible for securing your workloads and configuring your services (such as compute, network, storage, and database) securely.
In a fully isolated, single-tenant, bare metal server with no Oracle software on it, your responsibility increases as you bring the entire software stack (operating systems and above) on which you deploy your applications.
In this environment, you are responsible for securing your workloads, and configuring your services (compute, network, storage, database) securely, and ensuring that the software components that you run on the bare metal servers are configured, deployed, and managed securely.
More specifically, your and Oracle's responsibilities can be divided into the following areas: