What is IaaS?

Infrastructure as a Service (IaaS) is a cloud computing model in which a provider delivers virtualized compute, storage, and networking resources over the internet, and customers rent and manage those resources remotely instead of buying, hosting, and maintaining physical servers and network hardware themselves.

Key takeaways

• IaaS rents compute, storage, and networking instead of owning hardware.
• The provider manages physical infrastructure; the customer manages the OS and apps.
• AWS, Microsoft Azure, and Google Cloud Platform are leading IaaS providers.
• Usage-based billing lets capacity scale up or down with demand.
• Data stored in IaaS still needs its own access control, DLP, and threat protection.

On this page: Why it matters · How it works · Types · IaaS & Versa · FAQ

Why is IaaS important?

Before IaaS, running an application meant buying servers, storage, and network gear, racking it in a data center, and staffing people to keep it running – a slow, capital-intensive process that made it hard to react to demand. IaaS converts that fixed capital expense into a metered operating expense: a team provisions a virtual machine or storage volume in minutes through an API, and pays only for what it uses.

That elasticity is also why IaaS underpins most of the rest of the cloud – PaaS and SaaS offerings are themselves typically built on top of it. For security teams the tradeoff cuts both ways: IaaS removes the burden of hardware lifecycle management, but it also moves sensitive data onto infrastructure the organization doesn’t own, which is why data protection for IaaS has become its own discipline.

What is IaaS?

In the IaaS model, the provider owns and operates the physical layer – servers, storage arrays, network switches, and the hypervisors that virtualize them – inside its own data centers. The customer uses a self-service console, CLI, or API to provision virtual machines, block or object storage, and virtual networks, then manages everything above that layer: the operating system, middleware, runtime, and applications.

That division of responsibility distinguishes IaaS from the other cloud service models. PaaS goes a layer further, with the provider also managing the OS and runtime. SaaS goes further still, with the provider managing the entire application. IaaS sits at the bottom of that stack: maximum customer control over the software environment, minimum responsibility for the hardware underneath it.

Types of IaaS

IaaS deployments generally fall into three patterns. Public cloud IaaS runs on multi-tenant infrastructure operated by a provider – Amazon Web Services, Microsoft Azure, Google Cloud Platform, or Oracle Cloud Infrastructure – and shared across customers over the public internet; it’s the most common form because of its elasticity and pay-as-you-go pricing. Private cloud IaaS provides dedicated, single-tenant infrastructure, on-premises or hosted, for organizations with strict compliance or data-residency requirements. Hybrid and multicloud IaaS combines the two, or spans more than one public provider, so workloads can be placed for redundancy, cost, or regulatory reasons, or to avoid depending on a single vendor.

IaaS & Versa

Versa protects data in IaaS platforms – AWS, Microsoft Azure, Google Cloud Platform, and Oracle Cloud Infrastructure – through API-based data protection (API-DP), configured under a tenant in Versa Concerto. An API-DP policy for IaaS contains rules that are event-based, triggered by activity such as a file upload, or schedule-based, running a retro scan of objects already at rest in storage such as S3 buckets, Azure storage accounts, or OCI buckets. Each connector is registered through OAuth 2.0 so Versa can scan content against DLP and malware-sandboxing policies.

For IaaS platforms that are certificate-pinned or otherwise unreachable to inline inspection, Versa also supports offline CASB profiles for IaaS, acting on file-upload and file-delete activity through an authorized connector rather than a network-layer proxy – complementing the inline CASB enforced through VOS.

Frequently asked questions

What is the difference between IaaS, PaaS, and SaaS?

They differ in how much of the stack the provider manages. IaaS covers only the physical and virtualization layer, leaving the OS and above to the customer. PaaS also manages the OS and runtime. SaaS manages the entire application, leaving the customer to just use it.

What are examples of IaaS providers?

The largest public IaaS providers are Amazon Web Services (AWS), Microsoft Azure, Google Cloud Platform (GCP), and Oracle Cloud Infrastructure (OCI). Each offers virtual machines, block and object storage, and virtual networking that customers provision, configure, and manage themselves through a console, CLI, or API.

Is IaaS more secure than on-premises infrastructure?

Neither is inherently more secure; security depends on configuration. IaaS providers secure the physical infrastructure and hypervisor, but the customer remains responsible for securing what they deploy on top of it – operating systems, applications, network rules, identities, and the data itself.

How does Versa protect data stored in IaaS?

Versa configures API-based data protection policies per IaaS instance in Concerto, scanning objects in motion and at rest for DLP and malware violations, and offers offline CASB profiles that act on file-upload and file-delete activity for IaaS services that can’t be inspected inline.

What is the shared responsibility model in IaaS?

It’s the split between what the provider secures and what the customer secures. The provider is responsible for the physical data center, hardware, and virtualization layer; the customer is responsible for the OS, applications, identities, and data they run on top of it.

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