In this article, we will discuss the different cloud deployment models, and look at how you can choose the best one for your business based on your requirements, as well as investigate the pros and cons of each model.
A cloud deployment model essentially defines where the infrastructure for your deployment resides and determines who has ownership and control over that infrastructure. It also determines the clouds nature and purpose.
Each organization will have its own requirements when making the shift or starting its journey to the cloud. In order to avoid costly and time-consuming bad decisions, it is critical to understand the organizational needs before embarking on the journey to the cloud. Making good decisions in the planning stage can help your business accelerate growth, help your business goals, and maintain competitiveness.
Most businesses in 2022 will already have some presence in the cloud, for example commonly utilizing a mix of SaaS (Software-as-a-service) offerings, such as Azure Active Directory, Office 365, Gmail, or IaaS (Infrastructure-as-a-service) offerings, such as hosting infrastructure in Microsoft Azure or Amazon Web Services (AWS). Incorrect planning at the initial stages could put you at a disadvantage over your competitors who may be at a more mature stage in their cloud journey. The COVID-19 pandemic has accelerated business journeys to the cloud as workers connected to resources from home. During this process, different cloud deployment models had to be taken into account, with the speed of adoption commonly being the number one priority for many businesses.
The first port of call for any organization looking to adopt cloud services is to understand the available deployment models. Once these are understood, a better decision can be made about which routes the business should pursue. Each model will offer advantages and disadvantages in areas such as governance, scalability, security, flexibility, cost, and management.
Broadly deployment models can be split into 5 categories:
Let’s take a look at each model in more detail.
Public cloud is a commonly adopted cloud model, where the cloud services provider owns the infrastructure and openly provides access to it for the public to consume.
As the service provider owns the hardware and supporting networking infrastructure, it is under the service provider’s full control. The service provider is responsible for physical security, maintenance, and management of the data center where the infrastructure resides. The underlying infrastructure is therefore outside of the customer’s control and also away from the customer’s physical location.
The cloud service provider will share infrastructure between multiple customers, whilst keeping data separate and isolated, offering many layers of security controls where this is a concern. Some services can be hosted on dedicated or isolated hardware if required, usually at an additional cost. Cloud providers go to huge lengths to ensure physical datacenters are extremely secure and are highly regulated environments, almost always exceeding the standards a customer could achieve themselves.
Infrastructure is managed primarily using a web browser, but can also be manipulated using an API, on the command line, or using infrastructure-as-code tools such as Terraform.
Commonly used public clouds include Microsoft Azure, Amazon AWS, Google Cloud, Oracle Cloud, and Alibaba Cloud.
Pros and cons
+ Low initial capital cost (Move from Capex to Opex)
+ High Flexibility
+ High (almost unlimited) scalability
+ High Reliability
+ Low maintenance costs
– Data security concerns for strictly regulated businesses
A private cloud can be thought of as an environment that is fully owned and managed by a single tenant. This option is usually chosen to alleviate any data security concerns that might exist with the public cloud offering. Any strict governance requirements can also be more easily adhered to and the private cloud can be more easily customized. Full control of the hardware can lead to higher performance. A customer will typically run a private cloud within their own building (on-premises) or purchase rackspace in a data center in which to host their infrastructure.
However, the responsibility to manage the infrastructure also falls to the customer creating a need for more staff with wider skills and increasing costs. A large initial investment may also be required to purchase the required hardware.
Pros and cons
+ Increased security and control
+ Dedicated hardware may improve performance
+ High flexibility
– High cost
– Higher management overheads
The hybrid model combines both public and private cloud deployment models giving a single cloud infrastructure that is aimed at increasing flexibility and deployment options for the business. For example, applications with strict governance and data security requirements may be hosted in the business private cloud, whereas applications without these concerns which need to be scaled on demand, could be hosted in the public cloud. Benefits of both the public and private cloud can be realized, as well as some of the disadvantages such as increased management overhead and the initial challenge of setting up a hybrid infrastructure. Once realized, applications can be moved between infrastructure hosted in the public and private clouds, increasing flexibility and fault tolerance.
Typically businesses may have some presence on-premise, and utilizing this hardware until it has reached end-of-life in the private cloud will likely be an attractive option if the business already owns the hardware. In the hybrid model, this can be used to form part of the private cloud. Most businesses strive to alleviate the burden on the existing infrastructure, migrating to the public cloud where possible, effectively utilizing the hybrid deployment model during the migration period.
Pros and cons
+ Improved scalability
+ High control
+ Highly scalable
+ High fault tolerance
– Setup challenges
– High management overhead
The multi-cloud deployment model usually refers to the use of multiple public cloud providers to increase flexibility and fault tolerance, such as the use of Microsoft Azure, Amazon AWS, and Google Cloud. The private cloud can also be thrown into the mix to give extra reliability and flexibility.
Some services may be preferred on a certain cloud over another after evaluation by the business. For example, the GKE (Google Kubernetes Engine) hosted on the Google Cloud may be preferable over similar offerings on Azure such as AKS (Azure Kubernetes Service), or Amazon EKS (Elastic Kubernetes Service). Workloads can be distributed selectively. Adopting multiple clouds gives development teams a choice from a much wider pool of options, and can actually aid the developer workflow. Some comparable services may be cheaper than others and so may also be preferable in certain scenarios, for example, AWS could be used for production, and Google Cloud used for testing.
Multi-cloud is also commonly used by businesses with critical workloads, such as government agencies or financial corporations. Spreading data and infrastructure between multiple cloud providers can increase fault tolerance should one cloud platform encounter service outages. The benefits of the multi-cloud model can also be leveraged when a business forms a disaster recovery and business continuity plan.
However, with each option that is introduced, management becomes more complex and staff requires more skills to fully realize the benefits of a multi-cloud deployment model. Depending on the business objectives, multi-cloud has the potential to lower costs or raise them if increased fault tolerance is the goal. As with anything in I.T, the trade-off between the application requirements and the budget should be weighed up. Larger businesses further along the road in their cloud journey are usually suited to the multi-cloud model, as typically a business will adopt and single public cloud, and adopt another public cloud when the business requirements can be justified.
Pros and cons
+ Very high reliability
+ Very high flexibility
– Increased management complexity
– Increased staffing skills required
Learn more about multi-cloud benefits and best practices.
A lesser-known and less adopted deployment model, a Community cloud brings together infrastructure that is shared and jointly accessed by several organizations from a specific group that shares specific computing needs. For example, the education sector could utilize a community cloud to enable a group of scholars and students to share academic content, making joint research easier.
Pros and cons
+ Sharing infrastructure lowers costs
– Reduced security
– Not applicable to most SMEs (Small to Medium enterprises)
Understanding the available cloud deployment models is key to positioning your business for success.
In the real world, new businesses and startups will commonly opt to fully adopt the public cloud where possible. Most existing businesses will have some existing infrastructure presence on-premise, and therefore bringing this into a private cloud and adopting the hybrid model may make more sense. Private cloud is a high-cost option with high overheads but is sometimes a requirement where data security regulation or concerns about data sovereignty are paramount. Multi-cloud can be considered where high reliability is a concern, such as in the financial industry.
And if you need an automation layer for your cloud resources, take a look at Spacelift’s self-service infrastructure.
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Spacelift is an alternative to using homegrown solutions on top of a generic CI. It helps overcome common state management issues and adds several must-have capabilities s for infrastructure management.