Reviewing cloud deployment models
There are three main types of cloud deployment models available from cloud providers: public cloud, private cloud, and hybrid cloud (other cloud models exist, such as Community Cloud, but we won’t discuss those other models here). Here is a summary of these models:
- Public cloud:
- This is the most common model and where services and resources are offered over the public internet to anybody that wishes to purchase them. All cloud resources are owned and maintained by a cloud provider, so it’s more like renting resources than purchasing them.
- Pay only for what you use with a consumption-based model.
- The cloud provider handles maintaining and updating the hardware.
- Private cloud:
- Unlike the public model, services and resources are available exclusively for one organization. Often, this model is chosen when strict security controls and isolation are required.
- Hardware, software, configuration, maintenance, updates, and security are all managed by the organization exclusively using the available resources.
- Hardware needs to be purchased and all running costs fall to the organization if the hardware is running, even if resources aren’t being used.
- Hybrid cloud:
- You can compose public and private cloud models, taking advantage of the benefits of each.
- Flexibility to store sensitive information on private resources, while allowing interconnection to an application on the public cloud, for example.
- Ability to decide where to host workloads, depending on the requirements.
It’s important to note that although a private cloud may be required to meet certain regulatory standards, public clouds are often more than secure enough for most scenarios. The physical data centers hosting cloud hardware follow strict security controls that comply with many external regulations, as well as bring the benefits of availability and redundancy.
The security features available from cloud providers are comprehensive, industry-leading, and often offer better protection, monitoring, alerting, and remediation than most organizations achieve when they manage their resources. Unless otherwise stated, this book will be assuming that the public cloud is the chosen model (which is the most common by far).
Now that we understand the main cloud deployment models, of which the public cloud is the most common, we should discuss the service models available. You will encounter the models we are about to cover numerous times if you haven’t already, and every service you deploy in Azure will come under one of these models.
