Types of cloud computing
There are 4 main types of cloud computing: private clouds, public clouds, hybrid clouds, and multiclouds. There are also 3 main types of cloud computing services: Infrastructure-as-a-Service (IaaS), Platforms-as-a-Service (PaaS), and Software-as-a-Service (SaaS). Choosing a cloud type or cloud service is a unique decision. No 2 clouds are the same (even if they’re the same type), and no 2 cloud services are used to solve the same problem. But by understanding the similarities, you can be more informed about how the caveats of each cloud computing type and cloud service might impact your business.
What’s the same?
Every cloud abstracts, pools, and shares scalable computing resources across a network. Every cloud type also enables cloud computing, which is the act of running workloads within that system. And every cloud is created using a unique mix of technologies, which almost always includes an operating system, some kind of management platform, and application programming interfaces (APIs). Virtualization and automation software can also be added to every kind of cloud for additional capabilities or increased efficiencies.
What’s different?
The differences between public clouds, private clouds, hybrid clouds, and multiclouds were once easily defined by location and ownership. But it’s just not that simple anymore. So while we compare the differences below, there are plenty of caveats.
Public clouds
Public clouds are cloud environments typically created from IT infrastructure not owned by the end user. Some of the largest public cloud providers include Alibaba Cloud, Amazon Web Services (AWS), Google Cloud, IBM Cloud, and Microsoft Azure.
Traditional public clouds always ran off-premises, but today’s public cloud providers have started offering cloud services on clients’ on-premise data centers. This has made location and ownership distinctions obsolete.
All clouds become public clouds when the environments are partitioned and redistributed to multiple tenants. Fee structures aren’t necessary characteristics of public clouds anymore, since some cloud providers (like the Massachusettes Open Cloud) allow tenants to use their clouds for free. The bare-metal IT infrastructure used by public cloud providers can also be abstracted and sold as IaaS, or it can be developed into a cloud platform sold as PaaS.
Private clouds
Private clouds are loosely defined as cloud environments solely dedicated to a single end user or group, where the environment usually runs behind that user or group’s firewall. All clouds become private clouds when the underlying IT infrastructure is dedicated to a single customer with completely isolated access.
But private clouds no longer have to be sourced from on-prem IT infrastructure. Organizations are now building private clouds on rented, vendor-owned data centers located off-premises, which makes any location and ownership rules obsolete. This has also led to a number of private cloud subtypes, including:
Managed private clouds
Customers create and use a private cloud that’s deployed, configured, and managed by a third-party vendor. Managed private clouds are a cloud delivery option that helps enterprises with understaffed or underskilled IT teams provide better private cloud services and infrastructure.
Hybrid clouds
A hybrid cloud is a seemingly single IT environment created from multiple environments connected through local area networks (LANs), wide area networks (WANs), virtual private networks (VPNs), and/or APIs. The characteristics of hybrid clouds are complex and the requirements can differ, depending on whom you ask. For example, a hybrid cloud may need to include:
-
- At least 1 private cloud and at least 1 public cloud
- 2 or more private clouds
- 2 or more public clouds
- A bare-metal or virtual environment connected to at least 1 public cloud or private cloud
But every IT system becomes a hybrid cloud when apps can move in and out of multiple separate—yet connected—environments. At least a few of those environments need to be sourced from consolidated IT resources that can scale on demand. And all those environments need to be managed as a single environment using an integrated management and orchestration platform.
Multiclouds
Multiclouds are a cloud approach made up of more than 1 cloud service, from more than 1 cloud vendor—public or private. All hybrid clouds are multiclouds, but not all multiclouds are hybrid clouds. Multiclouds become hybrid clouds when multiple clouds are connected by some form of integration or orchestration.
A multicloud environment might exist on purpose (to better control sensitive data or as redundant storage space for improved disaster recovery) or by accident (usually the result of shadow IT). Either way, having multiple clouds is becoming more common across enterprises that seek to improve security and performance through an expanded portfolio of environments.
[Continue]