What Is Colocation-Based Infrastructure as a Service?

As IaaS evolves, colocation IaaS delivers greater control while allowing you to keep the advantages of public cloud

Efraim Martinez
David Tairych
What Is Colocation-Based Infrastructure as a Service?

The IaaS market has been growing for many years and is continuing to evolve to meet the requirements of today’s businesses. Not only has public cloud grown immensely in the last decade-plus, but the range of infrastructure solutions is growing as more organizations move away from private data centers toward shared infrastructure and distributed IT architectures. The data center colocation market is growing at a compound annual growth rate (CAGR) of 14.2%,[1] and the bare metal cloud market is forecast to grow at a CAGR of 41% globally between 2021–2025.[2]

There are numerous reasons for the growth of IaaS:

  • Predictable cost models: Organizations want to pay for what they use instead of making heavy investments in physical hardware that they might not need in the future.
  • Protecting existing investments: Companies want to get the most from their IT investments. IT infrastructure choices may be driven by their ability to protect investments they’ve already made in legacy applications.
  • Offloading infrastructure ownership and management: For many, it’s easier to let other vendors manage some aspects of IT infrastructure than to own and maintain it yourself.
  • Emerging tech applications: New AI and ML algorithms require powerful computing that can be supported by IaaS.
  • Demand for greener infrastructure: The interest in greater infrastructure efficiency is another fact that’s driving organizations toward choosing IaaS.

The IaaS landscape has changed since it was first introduced, and today, organizations have more choices about where to put infrastructure to support their needs. There are different types of IaaS available—the cloud-based IaaS that most people think of as well as colocation-based IaaS offerings. Bare Metal as a Service (BMaaS) is a specific type of colocation IaaS that’s appealing to companies that need greater control than public cloud can offer.

What exactly counts as IaaS, and how has it evolved?

Everyone in the IT world is familiar with a variety of “as a service” solutions—not just IaaS, but Platform as a Service (PaaS), Software as a Service (SaaS) and others. Among the cloud service models, IaaS is probably the most foundational and popular one.

Typically, what people refer to as “IaaS” is public cloud infrastructure that’s shared and virtual. IaaS, by definition, is a type of cloud computing that provides access to servers, storage and networking resources on demand, where customers can pay as they go. Cloud-based IaaS offerings are virtual systems that are managed by the cloud provider and delivered via virtual machines (VMs) over the internet. In cloud IaaS, the VMs are single-tenant, but the underlying platform is shared by multiple customers.

Since IaaS was first introduced, the types of available on-demand infrastructure in the market have expanded to meet the evolving needs of businesses. Today, there’s a wider variety of infrastructure options that fall under the IaaS umbrella. Not every workload is a fit for public cloud, and there are many scenarios where businesses want a greater degree of control over their infrastructure, but without having to run their own on-premises data center. So, in addition to public cloud IaaS, companies can now acquire IaaS from a colocation provider to create their hybrid cloud infrastructure.

Colocation-based IaaS is when a colocation company provides dedicated IT infrastructure resources on demand. With colocation IaaS, customers choose where their infrastructure is. Colocation providers can deliver an IaaS model that’s very similar to what public clouds provide—virtual, shared resources, except that you know where the infrastructure is in the physical world. Colocated Bare Metal as a Service (BMaaS)—or what’s sometimes called simply “bare metal” or bare metal cloud—is a special type of colocation IaaS. We’ll get into more of the distinctions below.

The fact that there are a variety of IaaS options is a great thing for businesses, because hybrid multicloud models are the standard today. Most companies use public cloud for some workloads but also want more control of others. Today, you have more choices about how to design your infrastructure to support the requirements of specific applications, high-performance, secure data storage and so on. And the workloads that you place outside the cloud still need to be adjacent to the cloud to support fast communication across your environment.

What’s the difference between traditional IaaS and IaaS from a colocation provider?

Cloud-based IaaS and colocation-based IaaS have some similarities and some differences. Both can be valuable parts of a hybrid cloud infrastructure, ensuring that workloads run on the optimal platform based on the application’s requirements. BMaaS, as a special type of colocation IaaS, overlaps with general colocation IaaS in some ways but also has some distinctions.

What are the similarities among all IaaS models? Well, in both cloud and colocation IaaS, the IT provider delivers on-demand IT infrastructure. And in both cases, customers get a very high level of agility compared to what private infrastructure can offer.

Now, let’s break down some of the differences:

  • Location: With cloud-based IaaS, you don’t know the exact location where your data lives. You might know the general region but not the specific data center. In contrast, with colocation-based IaaS, you choose exactly where to put infrastructure, and you can replicate a deployment in multiple data centers in key locations for your business.
  • Shared versus dedicated: With cloud IaaS, infrastructure is usually shared among multiple customers (what’s called multi-tenant), though a few cloud providers do offer bare metal instances. Colocation-based IaaS servers could be shared or dedicated. But BMaaS servers are dedicated to a single customer—that is, they’re single-tenant. With bare metal, you get access to 100% of the processing power, memory and storage of the physical hardware resources.
  • Virtual versus physical: Traditional cloud-based IaaS delivers virtual resources. Colocation IaaS could be virtual or physical, but BMaaS involves physical resources.

As you can see, BMaaS is a special type of colocation IaaS that has some unique traits among all the IaaS models available.

What are the benefits of colocation-based IaaS?

Now that we’ve covered what’s different about colocation IaaS—specifically bare metal—let’s talk about why you might choose bare metal in a colocation facility.

Greater control and choice

With colocation IaaS, you get much greater control of your IT resources since you know where they are. This is even more true with BMaaS, since you determine what you’re procuring too—what CPU, what server, what graphic card and so forth. You get to decide on the design. You also choose the operating system and software, the hypervisor and the tools.

Because BMaaS is single tenant, it’s fully dedicated to your business, and you also have more control of your data. This level of fine-grained control is essential for applications that require a specific type of hardware or specific network functions to work. And control really means choice—it means you get to bring your own software and define most aspects of your infrastructure.

Reduced management and operational overhead

For all IaaS models, there’s a mix of responsibility for different aspects of managing and operating the infrastructure. In all cases, customers have less responsibility than they would have for fully owned and managed servers in a private data center.

Colocation data centers take care of the data center itself, including the power supply, cooling and security, as well as providing metrics and service logs, business applications and services, portals and APIs. With BMaaS specifically, the colocation provider takes care of the physical servers, networking and configuration—so you don’t have to have staff in every location where you deploy bare metal infrastructure. At Equinix, our BMaaS solution also gives you proximity to essential clouds and network services, as well as private connectivity options, to support your hybrid multicloud environment.

Interconnection and cloud adjacency

While some workloads aren’t suitable for the cloud, they still need to be close and well connected to your cloud deployments. Colocated IaaS excels in interconnection capabilities, because while infrastructure is deployed in a neutral facility, it can be connected, with minimum latency, to any cloud. At Equinix, customers can get cloud adjacent infrastructure combined with our software-defined interconnection services—and it can all be deployed in minutes.


Every organization is concerned with optimizing the value they get from their IT investments. Both cloud-based IaaS and colocation-based IaaS are based on an OPEX cost model, so you pay for what you use, and you’re not investing in physical equipment that you might not need later. From there, how to save the most money really depends on the use case. Sometimes cloud is more cost-effective, and sometimes bare metal is.

BMaaS at Equinix

Equinix Metal®—our BMaaS solution—offers all the perks of bare metal colocation IaaS described above. Specifically, with Equinix, you get several advantages:

  • A colocation provider with global reach: Equinix is a global company, and Equinix Metal is available in 27+ metros.
  • The opportunity for consistent global deployments: In other words, you can replicate the design of the deployment from one location to the next.
  • Cloud adjacency: BMaaS at Equinix gives you proximity to all the major public cloud providers, a must for customers with hybrid multicloud models.
  • Low-latency connectivity: Equinix Fabric® interconnection provides fast, agile connectivity for hybrid environments.
  • Rapid provisioning: With Equinix Metal, you can set up a service in minutes, on-demand, and quickly adjust when your business needs change.
  • A robust ecosystem of partners and service providers: At Equinix, you can connect with your current vendors and market-leading cloud, networking and IT services providers.
  • Sustainability: Equinix data centers are covered by 96% renewable energy globally. We also have a thermal efficiency commitment and are exploring cutting-edge cooling technologies.

According to a recent report from Enterprise Strategy Group, Equinix Metal delivers near cloud-like agility for workloads on low-latency, highly available bare-metal servers at a cost that is up to 72% lower than build-it-yourself (BIY) infrastructure and up to 56% lower than public cloud infrastructure-as-a-service (IaaS).

Learn more about Equinix Metal by downloading the Enterprise Strategy Group report.


[1] Data Center Colocation Market to Reach $155.40 Billion by 2030: Grand View Research Inc., Yahoo! Finance, June 14, 2023.

[2] The Global Bare Metal Cloud Market is expected to grow by $ 11.35 bn during 2021-2025, progressing at a CAGR of over 41% during the forecast period, Globe Newswire, June 14, 2021.

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Efraim Martinez Senior Principal Solutions Architect
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David Tairych Senior Solutions Architect
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