What Is the Cloud?

What is the cloud?

The definition of cloud is very broad, but it is used to describe the global network of servers, and each server has its unique function. The cloud is not a physical entity, but an extensive global network of remote servers. These servers are linked together to operate in the form of a single ecosystem. These servers are designed to store and manage data, run applications, or deliver content or services, such as streaming audio and video, mail, productivity software, or social media. Files and data can be accessed online from any device with the Internet, rather than from the local machine or personal computer so that can get information anytime and anywhere when you need it.

From video streaming, web applications, customer relationship management (CRM) systems, to mobile banking, inventory, big data analysis, etc., the cloud enables companies to focus on innovation and provide services more quickly and conveniently.

The so-called cloud computing refers to placing data, software, programs, or services on the Internet for users to access, rather than on physical hard drives, servers, or mainframes. Cloud computing allows data to be accessed anytime, anywhere through the Internet connection, no matter where the user is. At the same time, it also allows enterprises to flexibly allocate and dispatch resources according to changes in their needs.

How does cloud computing work?

Cloud computing is realized because of a technology called virtualization. Virtualization allows the creation of digital-only analog "virtual" computers that behave like physical computers with their hardware. The term for this type of computer is called a virtual machine. When implemented correctly, virtual machines on the same host will be sandboxed from another virtual machine, so they will not interact with each other at all, and files and applications from one virtual machine will not be displayed to other virtual machines, even if these the virtual machines are all located on the same physical machine, and this is still the case.

Virtual machines can also use the hardware hosting the virtual machines more efficiently. By running many virtual machines at once, one server will become many servers, and the data center will become the entire host of the data center, which can provide services for many organizations. Therefore, the cloud provider can immediately provide the use of the server to distant customers (these customers may have to use it in other ways before), and the customer can do so at a lower cost.

Even if an individual server fails, the cloud server should always be connected and always available. Cloud vendors will back up services on multiple machines and multiple regions. No matter which device is used, users can access cloud services through a browser or applications, and connect to the cloud through the Internet (that is, through many interconnected networks).

What is the different cloud computing deployment models?

• Public cloud (Suitable for individual users and small and medium-sized enterprises):
  • Open to the general public or the infrastructure of a large industrial group.
  • Using the sub-leasing and sharing model, many users from various organizations can access the service at the same time.
  • The cloud service provider owns and is responsible for maintaining and managing the service.
  • Provide on-demand capabilities so that resources can be dynamically allocated according to user needs.
  • It is installed in the computer room of a cloud service provider and can be accessed via the Internet.
  • Usually used for non-core applications or operations.
• Private cloud (Suitable for medical institutions, government agencies, financial institutions, and telecommunications companies):
  • The infrastructure dedicated to serving a single organization cannot be accessed by the outside world.
  • With a single-tenant model, only employees of the organization can access the private cloud to meet its various operational needs.
  • The agency bears the cost of its procurement, deployment, and maintenance.
  • Resources can be dynamically allocated according to the needs of users.
  • It can be set up in the computer room of a cloud service provider or set up on a physical server inside the enterprise.
  • Usually used for sensitive data or applications, and operations that require a high degree of control.
• Hybrid cloud (Suitable for companies that need to provide products and services to the outside world):
  • A model that combines public cloud and private cloud combines the reliability of private cloud with on-demand access of public cloud.
• Multiple clouds:
  Multi-cloud is a type of cloud deployment that involves the use of multiple public clouds. In other words, organizations that use multiple cloud deployments lease virtual servers and services from several external vendors.

What are the different cloud service models?

• Software as a Service (SaaS):
  SaaS is the most widely used model in the cloud. The application is hosted by the cloud service provider, and the application is accessed via the network or the Internet. The software used is not on the user’s computer but a server accessible via the Internet.
• Platform as a Service (PaaS):
  The PaaS cloud computing model provides a platform for users or enterprises to develop, test, manage and build their applications. Users can obtain the necessary computing resources, tools, and software to develop their applications. Like SaaS vendors, PaaS vendors are responsible for managing, maintaining, and controlling their cloud infrastructure and maintaining their security. Most of the targets of PaaS are application developers, so certain technical capabilities are required to use it.
• Infrastructure as a Service (IaaS):
  The IaaS cloud service model can provide users or enterprises with the required computing performance, virtual machine (VM), storage, and network. The servers it provides include both physical and virtual servers. IaaS is different from SaaS and PaaS. Its users must control the cloud infrastructure and maintain its security. IaaS service providers are responsible for maintaining the underlying infrastructure they provide, and users must purchase, install, and manage the operating systems, intermediary software, and tools they need to develop applications by themselves. The target customers of IaaS are professionals with highly technical capabilities, such as infrastructure or network architects.
• Function as a Service (FaaS):
  FaaS, also known as serverless computing, divides cloud applications into smaller components and runs them only when needed. FaaS or serverless applications are still running on the server, just like all models of cloud computing. But it is called "serverless" because it will not run on a dedicated machine and because the company that builds the application does not have to manage any servers.

Advantages derived from cloud computing

Since companies no longer need to purchase and maintain the computing infrastructure they need, they can significantly shorten the development and deployment time of their applications and services. Enterprises can concentrate on developing applications without burdening heavy infrastructure maintenance tasks to ensure that various software and tools are always kept up to date. With the cloud, business processes can be streamlined, so products and services can be brought to market faster, applications can be tested and deployed faster, and innovation capabilities can be further promoted.

1. On-demand self-service: Users can automatically schedule cloud computing resources according to their own needs and requirements, without having to communicate with cloud service providers in advance.
2. Extensive network access: Users can access a variety of friendly cloud functions on any platform via the Internet connection, whether through mobile phones, laptops, or desktop computers, and no matter where in the world.
3. Resource sharing: The cloud is a sub-rental and shared platform. This means that all users can use the same cloud service and get the number of resources they need without worrying about or knowing the exact location of the resources.
4. Rapid flexibility: At any time, users can increase or decrease the cloud resources they need as their scale expands or shrinks to meet business needs. Enterprises can quickly increase or decrease the level of storage, or switch from one service plan to another without drastically changing their existing IT infrastructure.
5. Metering service: To meet the growth of demand, cloud service vendors must be able to provide users who need more resources with the required number of resources to maintain their services. Based on a highly quantitative design, all resource usage or consumption is accurately monitored and managed, regardless of whether users or manufacturers have detailed records.