Still not sure which cloud deployment or service model would be a match for your business needs? Or maybe you’re not really at home with all the cloud-related concepts and need a straightforward guidebook that will make cloud computing clearer for you? You’ve come to the right place.
We’ve combined all cloud-related articles from our blog into this comprehensive guide for everyone who considers building a cloud-based solution or migrating their software to the cloud.
Without further ado, let’s move on to the first important concept you’ll surely come across when considering cloud adoption: the choice of a cloud deployment model.
What are the cloud deployment models?
Cloud comes in various shapes… or rather deployment models. Each one fits different business needs and it may be tricky to choose the most suitable one if you’re not well-versed in the topic.
A cloud deployment model specifies who has access to the infrastructure and uses it: whether it’s for your exclusive use or it’s a shared solution. It may also be a combination of both.
So, let’s now take a close-up look at four main cloud deployment models: public cloud, private cloud, hybrid cloud and multicloud and see how they differ in cost, easiness of setup, control level as well as scalability.
A public cloud is hosted by a third-party provider who manages the whole infrastructure: both the hardware and software. You can also manage it to a certain extent, but not like in a private cloud. The name “public cloud” means that the cloud service is accessible to the public, but the data stored in a public cloud isn’t available to everyone.
What level of control does a public cloud give? You can configure and to some extent manage the network, load balancing, or routers, but you can’t decide about what machine is allocated to you.
Some of the main pros of a public cloud in comparison to other deployment models are:
- no need to invest in and be responsible for hardware,
- cost efficient pay-per-use model,
- very high scalability,
- software licence included in the price
However, it’s important to remember that there may be some government policies, industry standards or legal requirements specific to your business niche that public cloud platforms may not be compliant with.
In the private cloud, you have the cloud infrastructure for your exclusive use. The servers are provided by a third-party vendor, for example, a data centre.
The key advantage of a private cloud deployment model is that it can be tailored to your needs thanks to flexible configuration options, allowing your solution to meet very specific business or legal requirements.
There’s another side to the coin, though. In the private cloud, you only get virtual machine and network access for a start. If you want to set up and manage the environment, you’re left to do it on your own. The SLA can be lower than in a public cloud and there are no pre-built solutions or additional services to help you make the setup and management easier. Therefore, to have everything up and running you’ll need the help of IT specialists.
If one of your needs is high scalability, a private cloud may be a less favourable option for you. The limited possibility of hardware extension makes it less scalable in comparison to a public cloud.
A hybrid cloud is a combination of a private and public cloud or a cloud with on-premise infrastructure. In this model all the infrastructures are connected, enabling data flow and integration.
A hybrid cloud offers the benefits, but also the downsides, of the two worlds. It’s cost-efficient because if you don’t need part of your resources, you can move it to on-premise and vice-versa. However, configuring a hybrid cloud and making sure that everything is smoothly linked together for example through a VPN is not easy and requires expert knowledge and skills.
It’s worth noting that a hybrid cloud model can be useful when migrating your business to the cloud as it ensures the continuity of processes.
Multicloud refers to using more than one cloud from multiple vendors.
Multicloud may be a model worth considering if you’re looking to optimize the cost or to gain a competitive advantage. One cloud deployment model may better address your requirements for solution A, while the other one – for solution B. The only challenge is a tricky cross-cloud connection that requires expert knowledge and skills.
What are the cloud service models?
A cloud service model specifies the scope of control over and responsibility for the infrastructure and data that can either be more on your side or the provider’s side, depending on your needs.
SaaS vs PaaS vs IaaS: pros and cons
Infrastructure as a Service (IaaS)
IaaS (Infrastructure as a Service) model gives you access to servers, storage, network and includes virtualization. Your developers’ job is to take care of the operating system, middleware, runtime, data and application itself.
The advantages of IaaS are:
- It’s easier to manage than on-premise things related to security or configurations are handled by a vendor.
- It offers flexibility as it’s the most customizable option out of the three cloud service models.
- You don’t have to worry so much about vendor lock-in because you aren’t so closely tied to a specific cloud provider.
- IaaS is a good solution for migrating legacy apps that aren’t cloud-ready because it’s flexible to configure.
However, high flexibility entails additional responsibility on your side. In IaaS your developers are in charge of keeping the environment up to date and do regular backups as part of the maintenance tasks.
Platform as a Service (PaaS)
PaaS provides your developers with the components for developing your software. You don’t have to worry about servers, storage, operating system, runtime, or virtualization. Your developers can instead focus their efforts on developing software.
The benefits of PaaS include:
- Shorter deployment time because you don’t have to create and configure your own work environment. You can use ready-made tools or options to do some routine tasks.
- No need to worry about system or component upgrades. It’s all vendor’s duty.
- In many cases, PaaS solutions are easier to scale than IaaS or SaaS.
PaaS solutions also have some limitations. The older applications may not work well in this model, and eventually, during the migration, they may need to be refactored or rewritten. Also, with PaaS, in most cases, you become tied to and dependent on a single vendor.
Software as a Service (SaaS)
In SaaS, the provider develops and manages the software in the cloud environment and takes care of its maintenance. As a customer, you get a ready-made product. Everything else is the provider’s responsibility.
SaaS offers two main benefits:
- It’s an up-and-running solution that doesn’t need development or handling the hosting by your team.
- There are no initial setup costs because everything is covered within the monthly subscription.
As with any ready-made solution, SaaS also has its downsides. The major one is limited customization. You can’t really have it tailored to your specific business needs. The other disadvantage of this model is no control over the infrastructure. You have to trust the vendor in everything.