On-Premises, Colocation, IaaS, PaaS or SaaS?

About this interactive

Virtualization opened the door to the cloud, and today an organization can hire out as much or as little of its infrastructure as it likes. The models line up from doing everything yourself to doing almost nothing. On-premises: you run it all, the room, the AC, the UPSs, the ISP link, the hardware and the software. Colocation: you rent space, racks, power and cooling in someone else's data center, and put your own equipment in it, still under your control. IaaS: the provider runs the data center, network, storage, servers and hypervisor, and rents you virtual machines. You pick a region, an operating system and an instance size, and everything from the OS up is yours. PaaS: the provider also runs the operating system and the runtime, as RDS runs SQL Server for you, so you bring the application and its data. SaaS: the provider runs the application too, as with Microsoft 365, Salesforce or Zoom, and you use it in a browser or a light app. To sort a card, find the lowest layer the customer still runs.

What you'll learn

Identify an infrastructure arrangement as on-premises, colocation, IaaS, PaaS or SaaS from who runs which part of it
Recognize how each step from on-premises to SaaS hands more of the stack to a provider: the facility in colocation, the hardware and hypervisor in IaaS, the operating system and runtime in PaaS, and the application in SaaS

Aligned to

CompTIA Security+

3.1 Compare and contrast security implications of different architecture models.

Key terms

On-Premises: An infrastructure deployment model in which hardware and software are hosted locally within an organization's own facilities rather than in a cloud provider's data center. On-premises deployments give organizations full control over their security posture.
Colocation: A data center model in which an organization rents physical space, power, cooling, and network connectivity from a third-party facility while retaining ownership of its own servers and equipment.
Infrastructure as a Service: A cloud service model that provides virtualized computing infrastructure over the internet.
Platform as a Service: A cloud service model that provides a platform for developing, running, and managing applications without managing infrastructure.
Software as a Service: A cloud service model that delivers software applications over the internet on a subscription basis.
Instance: A single virtual server provisioned within an IaaS platform, configurable by attributes such as region, operating system, and compute size.
EC2: Amazon Web Services' IaaS offering that allows users to provision and manage virtual machines with full control over the operating system and installed software.
RDS: Amazon Web Services' PaaS relational database offering that manages the underlying infrastructure and database engine, allowing users to interact with the database without managing the OS or server.

Topics

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