What is cloud computing?

Cloud computing is on-demand access over the Internet to computing resources - applications, servers (physical servers and virtual servers), data storage, development tools, networking capabilities, and more - hosted in a remote data center managed by cloud services. provider (or CSP). CSP makes these resources available for a monthly subscription or bills based on usage.

Compared to traditional on-premises IT infrastructure and depending on the chosen cloud services, cloud computing helps to accomplish the following tasks:

Reduced IT costs. The cloud allows you to remove some or most of the cost and effort of acquiring, installing, configuring and managing your own on-premises infrastructure.
Increase flexibility and ROI. With the cloud, your organization can start using enterprise applications in minutes, rather than waiting weeks or months for IT to respond to a request, purchase and configure ancillary hardware, and install software. The cloud also allows some users - especially developers and data scientists - to help themselves develop software and maintain infrastructure.
Easier and more economical scalability. The cloud provides elasticity - instead of buying excess capacity that isn't used during slow periods, you can scale capacity up and down in response to spikes and dips in traffic. You can also take advantage of your cloud provider's global network to distribute your applications closer to users around the world.

The term cloud computing also refers to the technology that makes the cloud work. This includes some form of virtualized IT infrastructure — servers, operating system software, networks, and other infrastructure — that is abstracted away using specialized software so that it can be combined and shared regardless of the physical boundaries of the hardware. For example, one hardware server can be split into multiple virtual servers.

Virtualization enables cloud service providers to make the most of their data center resources. Unsurprisingly, many corporations have adopted a cloud delivery model for their on-premises infrastructure to maximize utilization and cost savings over traditional IT infrastructure and offer end users the same self-service and flexibility.

If you use a computer or mobile device at home or work, you almost certainly use some form of cloud computing every day, be it a cloud app like Google Gmail or Salesforce, streaming media like Netflix, or cloud file storage like this. like Dropbox. According to a recent survey, 92% of organizations are using the cloud today (link is external), and most of them plan to use it even more in the next year.

SaaS (software as a service)

SaaS - also known as cloud software or cloud applications - is application software that is hosted in the cloud and that you receive and use through a web browser, a dedicated desktop client or API that integrates with your desktop or mobile operating system. In most cases, SaaS users pay a monthly or annual subscription fee; some may offer pay as you go.

In addition to the benefits of cloud savings, ROI and scalability, SaaS offers the following:

Automatic updates: With SaaS, you can take advantage of new features as soon as the vendor adds them, without having to orchestrate a local update.
Data Loss Prevention: Since your app's data is in the cloud, you won't lose data with the app if your device crashes or breaks.

SaaS is the primary delivery model for most commercial software today - hundreds of thousands of SaaS solutions are available, from the most specialized industry and departmental applications to powerful enterprise software databases and AI (artificial intelligence) software.

PaaS (Platform as a Service)

PaaS provides software developers with a platform on demand — hardware, a complete software stack, infrastructure, and even development tools — to run, develop, and manage applications without the cost, complexity, and inflexibility of maintaining that platform locally.

With PaaS, the cloud provider hosts everything - servers, networks, storage, operating system software, middleware, databases - in their data center. Developers simply choose from menus to spin up the servers and environments they need to run, build, test, deploy, maintain, update, and scale their applications.

PaaS today is often built around containers, a virtualized computing model that is one step away from virtual servers. Containers virtualize the operating system, allowing developers to package an application with only the operating system services it needs to run on any platform, without modification or middleware.

Red Hat OpenShift is a popular PaaS built on Docker and Kubernetes containers, an open source container orchestration solution that automates deployment, scaling, load balancing, and more for container-based applications.

IaaS (infrastructure as a service)

IaaS provides on-demand access to core computing resources — physical and virtual servers, networks, and storage — over the Internet on a pay-as-you-go basis. IaaS allows end users to scale and scale down resources as needed, reducing the need for high upfront capital expenditures or unnecessary on-premises or “proprietary” infrastructure, as well as outsourcing resources to compensate for periodic spikes in usage.

Unlike SaaS and PaaS (and even newer PaaS computing models such as containers and serverless), IaaS gives users the lowest level of control over computing resources in the cloud.

IaaS was the most popular cloud computing model when it emerged in the early 2010s. While it remains a cloud model for many types of workloads, SaaS and PaaS usage is growing much faster.

Serverless Computing

Serverless computing (also called simply serverless) is a cloud computing model that shifts all the tasks of managing the server infrastructure - provisioning, scaling, scheduling, patching - to the cloud service provider, allowing developers to focus all their time and effort on code and business logic, specific to their applications.

Moreover, the serverless runs application code only for each request and automatically scales the supporting infrastructure up and down in response to the number of requests. In serverless mode, customers only pay for resources used while the application is running - they never pay for idle capacity.

FaaS, or feature as a service, is often confused with Serverless Computing, when in reality it is a subset of Serverless Computing. FaaS allows developers to execute pieces of application code (called functions) in response to certain events. Everything but the code - the physical hardware, the virtual machine operating system, and the web server software management - is automatically provided by the cloud provider in real time as the code is executed and rolled back once the execution is complete. Billing starts when execution starts and stops when execution stops.

Public cloud

A public cloud is a type of cloud computing in which a cloud provider makes computing resources - from SaaS applications to individual virtual machines (VMs) to non-operating system computing hardware to complete enterprise-grade infrastructure and development platforms - available to users. via the public Internet. These resources can be made available for free, or access can be sold under subscription or pay-per-use pricing models.

The public cloud provider owns, operates, and assumes full responsibility for the data centers, hardware, and infrastructure that run its customers' workloads, and typically provides broadband network connectivity to provide high performance and fast access to applications and data.

The public cloud is a multi-tenant environment — the cloud provider's data center infrastructure is used by all public cloud customers. In the leading public clouds - Amazon Web Services (AWS), Google Cloud, IBM Cloud, Microsoft Azure, and Oracle Cloud - these customers can number in the millions.

The global public cloud computing market has grown exponentially over the past few years, and analysts predict this trend will continue; Industry analyst Gartner predicts global public cloud revenues to surpass $ 330 billion by the end of 2022 (link is external).

Many enterprises are migrating portions of their computing infrastructure to the public cloud because public cloud services are resilient and highly scalable, flexibly adapting to changing workload demands. Others are attracted by the promise of more efficiency and less wasted resources, as customers only pay for what they use. Still others seek to reduce costs for equipment and local infrastructure.

Private cloud

A private cloud is a cloud environment in which all cloud infrastructure and computing resources are dedicated and available to only one customer. A private cloud combines many of the benefits of cloud computing, including elasticity, scalability, and ease of service delivery, with access control, security, and resource provisioning on-premises infrastructure.

A private cloud is usually hosted on-premises in the customer's data center. But a private cloud can also be hosted on an independent cloud provider's infrastructure, or built on leased infrastructure hosted in an external data center.

Many companies prefer a private cloud over a public cloud because a private cloud is the easier (or only) way to ensure compliance. Others choose a private cloud because their workloads involve sensitive documents, intellectual property, personal information (PII), medical records, financial data, or other sensitive data.

By building a private cloud architecture in accordance with the principles of a native cloud, the organization gives itself the flexibility to easily move workloads to the public cloud or run them in a hybrid cloud environment (see below) when they are ready.

Hybrid cloud

Hybrid cloud is what it sounds like - a mix of public and private clouds. Specifically, and ideally, a hybrid cloud connects an organization's private cloud services and public clouds into a single flexible infrastructure to run the organization's applications and workloads.

The goal of a hybrid cloud is to create a mix of public and private cloud resources - and with some level of consistency between them - that gives an organization the flexibility to choose the right cloud for each application or workload and move workloads freely between them. clouds as circumstances change. This enables an organization to achieve its technical and business goals more efficiently and at a lower cost than using only the public or private cloud.