Cloud Deployment Model - Private , Public, Hybrid Clouds

Cloud deployment models: public clouds, private clouds, community clouds, and hybrid clouds. A cloud deployment model is defined according to where the infrastructure for the deployment resides and who has control over that infrastructure.
A cloud deployment model is a specific configuration of environment parameters such as the accessibility and proprietorship of the deployment infrastructure and storage size. This means that deployment types vary depending on who controls the infrastructure and where it's located.

1. Public Cloud

The name speaks for itself: public clouds are available to the general public, and data are created and stored on third-party servers. Server infrastructure belongs to service providers that manage it and administer pool resources, which is why there is no need for user companies to buy and maintain their own hardware. Provider companies offer resources as a service both free of charge or on a pay-per-use basis via the Internet. Users can scale resources as required. The public cloud deployment model is the first choice for businesses with low privacy concerns. When it comes to popular public cloud deployment models, examples are Amazon Elastic Compute Cloud (Amazon EC2 - the top service provider according to ZDNet), Microsoft Azure, Google App Engine, IBM Cloud, Salesforce Heroku and others.

The Advantages of a Public Cloud

Hassle-free infrastructure management. Having a third party running your cloud infrastructure is convenient: you do not need to develop and maintain your software because the service provider does it for you. In addition, the infrastructure setup and use are uncomplicated.
High scalability. You can easily extend the cloud's capacity as your company requirements increase.
Reduced costs. You pay only for the service you use, so there's no need to invest in hardware or software.
24/7 uptime. The extensive network of your provider's servers ensures your infrastructure is constantly available and has improved operation time.

The Disadvantages of a Public Cloud

Compromised reliability. That same server network is also meant to ensure against failure But often enough, public clouds experience outages and malfunction, as in the case of the 2016 Salesforce CRM disruption that caused a storage collapse.
Data security and privacy issues give rise to concern. Although access to data is easy, a public deployment model deprives users of knowing where their information is kept and who has access to it.
The lack of a bespoke service. Service providers have only standardized service options, which is why they often fail to satisfy more complex requirements.

2. Private Cloud

There is little to no difference between a public and a private model from the technical point of view, as their architectures are very similar. However, as opposed to a public cloud that is available to the general public, only one specific company owns a private cloud. That is why it is also called an internal or corporate model.
The server can be hosted externally or on the premises of the owner company. Regardless of their physical location, these infrastructures are maintained on a designated private network and use software and hardware that are intended for use only by the owner company.
A clearly defined scope of people have access to the information kept in a private repository, which prevents the general public from using it. In light of numerous breaches in recent years, a growing number of large corporations has decided on a closed private cloud model, as this minimizes data security issues.
Compared to the public model, the private cloud provides wider opportunities for customizing the infrastructure to the company's requirements. A private model is especially suitable for companies that seek to safeguard their mission-critical operations or for businesses with constantly changing requirements.
Multiple public cloud service providers, including Amazon, IBM, Cisco, Dell and Red Hat, also provide private solutions.
At SaM Solutions, we have created an efficient ready-to-use Platform as a Service, the SaM CloudBOX. This PaaS facilitates projects via quick and easy launching and allows companies to make the most of BizDevOps.

The Benefits of a Private Cloud

All the benefits of this deployment model result from its autonomy. They are the following:

Bespoke and flexible development and high scalability, which allows companies to customize their infrastructures in accordance with their requirements
High security, privacy and reliability, as only authorized persons can access resources.

The Drawbacks of a Private Cloud

The major disadvantage of the private cloud deployment model is its cost, as it requires considerable expense on hardware, software and staff training. That is why this secure and flexible computing deployment model is not the right choice for small companies.

3. Community Cloud

A community deployment model largely resembles the private one; the only difference is the set of users. Whereas only one company owns the private cloud server, several organizations with similar backgrounds share the infrastructure and related resources of a community cloud.

If all the participating organizations have uniform security, privacy and performance requirements, this multi-tenant data center architecture helps these companies enhance their efficiency, as in the case of joint projects. A centralized cloud facilitates project development, management and implementation. The costs are shared by all users.

The Strengths of a Community Cloud

Cost reduction
Improved security, privacy and reliability
Ease of data sharing and collaboration

The Shortcomings of a Community Cloud

High cost compared to the public deployment model
Sharing of fixed storage and bandwidth capacity
Not commonly used yet

4. Hybrid Cloud

As is usually the case with any hybrid phenomenon, a hybrid cloud encompasses the best features of the abovementioned deployment models (public, private and community). It allows companies to mix and match the facets of the three types that best suit their requirements.

As an example, a company can balance its load by locating mission-critical workloads on a secure private cloud and deploying less sensitive ones to a public one. The hybrid cloud deployment model not only safeguards and controls strategically important assets but does so in a cost- and resource-effective way. In addition, this approach facilitates data and application portability.