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Not all clouds are created equal, where do your workloads belong?


Sometimes things can get a little confusing in the cloud. In this article, Leigh Plumley, CRO at Aptum explores which workloads belong in the public cloud, private cloud, on-premises and SaaS.

Organisations are continuing to leave behind traditional compute, storage and networking infrastructure in pursuit of cloud transformation.

Aptum’s recent Cloud Impact Study surveyed 400 senior IT professionals and found that efficiency (72%), increased agility (56%) and increased security (51%) were the main drivers behind cloud adoption.

But not all applications can be seamlessly and generically moved over to ‘the cloud’. Different workloads operate best on different infrastructures, and a bespoke approach to the migration and optimisation of those workloads is required.

Analyst firm Gartner recently recommended IT leaders consider shifting approaches from ‘cloud-first’ to ‘cloud-smart’.

This means ensuring a company’s business goals and cloud adoption strategy are aligned, as well as staying aware of different cloud infrastructure capabilities.

With a number of hosting options available, cost, compliance, security and performance, as well as data requirements, need to be taken into account when deciding which applications will be placed on which infrastructure.  

I’ve outlined four infrastructure options below, each of which serves a different purpose depending on your needs: public cloud software-as-a-service (SaaS); public cloud infrastructure-as-a-service (IaaS) and platform-as-a-service (PaaS); private cloud; and on-premises – alongside the importance of having the right workloads in the right place for the right reason.

Public cloud SaaS

The first thing you need to know when considering moving an application or business process to the cloud is whether functionality will increase because of the move. 

SaaS eliminates the need to oversee traditional IT infrastructure, meaning that if the process can function highly on the cloud, your business is freed up to improve other areas.

Public cloud SaaS is one of the fastest growing types of cloud service, with Gartner forecasting it to grow 18% in 2021 alone.

It has been a great option for organisations looking to quickly move generic back-office applications to the cloud to enable remote working without needing staff to manage infrastructure within a data centre.

The flexibility, ease of management and low cost of entry are key selling points of public cloud SaaS. Although ongoing operational costs can equate to the same expense as a traditional software offering, the positives of SaaS applications outweigh the negatives for many businesses’ workload requirements.

Public cloud IaaS and PaaS

Public cloud IaaS and PaaS offerings provide platforms for organisations to run and manage applications without the capital expense of physical infrastructure. Like all public cloud solutions, IaaS and PaaS offer no up-front costs and excellent scalability.

PaaS delivers a framework that developers can use to build customised applications without worrying about managing servers and storage, as well as security, middleware, development tools, etc.

IaaS, on the other hand, offers customers virtualised cloud infrastructure, where they can manage and monitor applications, operating systems and data. If you need more resources to run your applications, you can add them with the click of a button.

Public cloud IaaS and PaaS are ideal for test/development environments. For example, a company moving over to a service such as AWS Lambda doesn’t need to worry about any infrastructure at all. As a result, its programmers can focus on developing code, with the Lambda service scaling automatically. 


More and more companies are switching from on-premises to the cloud, with 59% of respondents to Aptum’s Cloud Impact Study stating they were both planning on reducing their on-premises infrastructure and switch to cloud-based solutions.

However, moving workloads to the cloud isn’t always simple or suitable for some organisations.

A manufacturer utilising third-party applications for industrial automation can’t ask the applications providers to re-architect its software to run on Azure. Third-party licensed software relies on the infrastructure for which it was designed to be run on.

In these limited circumstances, it can be more cost-effective to continue using a legacy on-premises service, at least until the business processes which rely on third-party applications can be rearchitected to fit a cloud environment.

Private cloud

Many situations require companies to have more control over the physical infrastructure on which its data is stored, as well access to bespoke services the infrastructure provides.

In these cases, private cloud is often the optimal choice over a public solution. Our Cloud Impact Survey found 66% of companies are planning on expanding their private cloud infrastructure, highlighting the growing popularity of tailored solutions.

One example would be moving a database application from a legacy environment to the public cloud. Database applications with a high input/output (I/O) requirement – where there are large volumes of reads and writes – could require a high-performance cloud environment, which can become expensive.

Companies can easily find themselves spending thousands every month to operate their databases if they don’t optimise the infrastructure.

There have even been cases where we have helped companies migrate back from the public cloud to a hybrid public/private cloud solution. Workloads with high I/O can create unpredictable and fluctuating costs on the pay-what-you-use model of public cloud.

Therefore, hosting these high activity services on fixed rate private infrastructure, while more consistent workloads remain on the public cloud, allows organisations to take advantage of the benefits from both services and keep budgets under control.

An example of this hybrid approach is an advertising technology firm we work with. They operate a self-service platform that allows buyers to purchase ads in real-time.

From the start, this customer ran a hybrid cloud model. A private cloud hosts their high-performance database, which needs to be constantly optimised and tuned, and the public cloud hosts their self-service ad buying platform that needs to be accessed by clients around the world in near real-time.

Private clouds are also ideal for compliance purposes. For example, if a company is required to hold data in a particular country because of regulatory requirements, a private infrastructure hosts all this data in one easily accessible and visible place.

Pick the right solution for your data requirements

The cloud offers clear benefits for every company and for particular business processes or applications.

While there are still instances where legacy infrastructure is a better option, many companies are reducing their on-premises infrastructure which means cloud solutions will continue to increase in popularity.

The decision of which solution works best for you revolves around issues like data sovereignty, security, performance, cost and control. Legacy infrastructure, public cloud, private cloud, or a hybrid approach – it’s all about ensuring the right workloads are in the right place for the right reason.

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