Overview of Cloud Deployment Models

Deployment Models

Deployment models indicate where the infrastructure resides, who owns and manages it, and how cloud resources and services are made available to users. The four cloud deployment models include—Public Cloud, Private Cloud, Community Cloud and Hybrid Cloud.

In this article, I would be discussing about Public Cloud, Private Cloud and Hybrid Cloud Models which are the three major deployment models.

This overview is based on my coursera class materials.

Let's get to the discussion

Public Clouds

In a public cloud model, users get access to servers, storage, network, security, and applications as services delivered by cloud service providers over the internet. Using web consoles and APIs, users can provision the resources and services they need.

The cloud provider owns, manages, provisions, and maintains the infrastructure, renting it out to customers either for a subscription charge or usage-based fee. Users don’t own the servers their applications run on or storage their data consumes, or manage the operations of the servers, or even determine how the platforms are maintained.

Public clouds offer significant cost savings in terms of Total Cost for Ownership (TCO) as the provider bears all the capital, operational, and maintenance expenses for the infrastructure and the facilities they are hosted in. It makes scalability as easy as requesting more capacity.

However, with a public cloud, the user does not have any control over the computing environment and is subject to the performance and security of the cloud provider’s infrastructure. There are several public cloud providers in the market today, such as Amazon Web Services, Microsoft Azure, IBM Cloud, Google Cloud Platform, and Alibaba Cloud.

Characteristics of a public cloud:

A public cloud is a virtualized multi-tenant architecture enabling tenants or users to share computing resources, residing outside their firewalls.

The cloud provider's pool of resources, including infrastructure, platforms, and software, are NOT dedicated for use by a single tenant or organization Resources are distributed on an as-needed basis offered through a variety of subscription and pay-as-you-go models.

Common use cases for public cloud

1. Organizations are increasingly opting to access cloud-based applications and platforms so their teams can focus on building and testing applications, and reducing time-to-market for their products and services.

2. Businesses with fluctuating capacity and resourcing needs are opting for the public cloud.

3. Organizations are using public cloud computing resources to build secondary infrastructures for disaster recovery, data protection, and business continuity.

4. More and more organizations are using cloud storage and data management services for greater accessibility, easy distribution, and backing up their data.

5. IT departments are outsourcing the management of less critical and standardized business platforms and applications to pubic cloud providers.

Private clouds

The National Institute of Standards and Technology defines private cloud as cloud infrastructure provisioned for exclusive use by a single organization comprising multiple consumers, such as the business units within the organization. It may be owned, managed, and operated by the organization, a third party or some combination of them, and it may exist on or off premises. Private cloud platforms can also be implemented internally or externally.

When the platform is provisioned over an organization's internal infrastructure, it runs on-premises and is owned, managed, and operated by the organization. When it is provisioned over a cloud providers infrastructure, it is owned, managed, and operated by the service provider. This external private cloud offering that resides on a cloud service providers infrastructure is called a Virtual Private Cloud or VPC.

A VPC is a public cloud offering that lets an organization establish its own private and secure cloud-like computing environment in a logically isolated part of a shared public cloud. Using a VPC, organizations can leverage the dynamic scalability, high availability, and lower cost of ownership of a public cloud, while having the infrastructure and security tailored to the organization's unique needs. Virtual Private Cloud are offered by most public cloud providers, such as IBM and Amazon.

Benefits of Private Cloud

A private cloud is a virtualized environment modeled to bring in the benefits of a public cloud platform without the perceived disadvantages of an open-end shared public platform. Users of a private cloud, such as developers and business units in an organization still get to leverage benefits such as economies of scale, granular scale, operational efficiencies, and users self-service while exercising full control over access, security and compliances specific to their organization and business. Private cloud provide you with:

1. The ability to leverage the value of cloud computing using systems that are directly managed or under perceived control of the organization's internal IT.

2. The ability to better utilize internal computing resources, such as the organization's existing investments in hardware and software, thereby reducing costs.

3.Better scalability through virtualization and cloud bursting. That is, leveraging public cloud instances for a period of time, but returning to the private cloud when the surge is meet.

4. Controlled access and greater security measures customized to specific organizational needs.

5. The ability to expand and provision things in a relatively short amount of time, providing greater agility.

6. Organizations may choose to opt for private cloud because of various reasons, because their applications provide a unique competitive advantage. There are security and regulatory concerns, or because their data is highly sensitive and subject to strict industry or governmental regulations.

Use cases for a private cloud.

1. a private cloud is an opportunity for organizations to modernize and unify their in-house and legacy applications. Moving these applications from their dedicated hardware to the cloud also allows them to leverage the power of the compute resources and multiple services available on the cloud.

2. Using the private cloud, organizations are integrating data and application services from their existing applications with public cloud services. This allows them to leverage their private cloud's compute capability for the larger jobs while pulling data into an application on a private cloud to leverage public cloud services. Essentially, opening their data centers to work with cloud services.

3.Application portability is a key feature of cloud platforms. Using the private cloud gives organizations the ability to build applications anywhere and move them anywhere without having to compromise security and compliance in the process.

4. Some of the key reasons that may prevent an organization for moving to a public cloud include security and regulatory concerns and data sensitivity. A private cloud offers these organizations the benefits of on-demand enterprise resources while exercising full control over critical security and compliance issues from within the environment of their dedicated cloud.

Hybrid Clouds

Hybrid Cloud is a computing environment that connects an organization's on-premise private Cloud and third-party public Cloud, into a single flexible infrastructure for running the organizations applications and workloads. The mix of public and private Cloud resources gives organizations the flexibility to choose the optimal Cloud for each application or workload.

Leveraging public Cloud instances for a period of time, but returned to the private Cloud when the search is met, also known as Cloud bursting.

A hybrid Cloud is portable.

Since you're no longer locked in with a specific vendor, you can move applications and data not just between on-premise and Cloud systems, but also between Cloud service providers. Hybrid is about taking the best of both worlds.

There are two common types of hybrid Clouds, hybrid mono Cloud and hybrid multi-Cloud.

Hybrid mono cloud is a hybrid cloud with one cloud provider while a hybrid multi-cloud is an open standards-based stack that can be deployed on any public Cloud infrastructure. The difference lies in the flexibility that the hybrid multi-Cloud offers organizations to move workloads and environments from one vendor to another.

There's also a variant of hybrid multi-Cloud called the composite multi-Cloud. It distributes single sub-applications across multiple providers, allowing you to move application components across Cloud services and vendors as needed.

Benefits of Hybrid Clouds

Hybrid Cloud offers significant benefits in areas of security and compliance, scalability and resilience, resource optimization and cost-saving.

1. A hybrid Cloud lets organizations deploy highly regulated or sensitive workloads in a private Cloud while running the less sensitive workloads on a public Cloud.

2. Because you're not locked in with a specific vendor and also don't have to make either/or decisions between the different Cloud models, you can make the most cost efficient use of your infrastructure budget.

3. You can maintain workloads where they are most efficient, spin up environments using Pay-As-You-Go in the public Cloud, and rapidly adopt new tools as you need them.

However, hybrid Clouds are complex and challenging to deploy and maintain since they involve synchronization, redirection, latency, security, portability, interoperability, and compatibility of policies, applications and data and so on. Connectivity and interoperability are core concepts of hybrid Cloud architectures.