IaaS, PaaS, SaaS – What’s The Difference?

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At a very high level, these are acronyms for different cloud computing models. They represent different levels of shared responsibility that a cloud user has with a cloud provider. According to Gartner, the growth of public cloud services worldwide in 2021 is set to grow around 23.1%.

What is IaaS (Infrastructure as a Service)?

This model is the closest to managing physical servers. The cloud provider is responsible for the physical hardware, but the cloud user is responsible for managing network configuring / OS maintenance etc. Being able to rapidly deploy compute resources is a distinct advantage of IaaS over procuring hardware and configuring it.

IaaS is considered the most flexible model. Being able to quickly provision computing resources without having to purchase and configure hardware is an excellent example of both flexibility and elasticity.

A good example of IaaS would be a company that provisions a number of virtual machines within Azure or AWS. Those servers may be used to then provide services such as hosting a website or providing file and print services.

Amazon AWS, Microsoft Azure are a few very well-known IaaS providers.

Advantages and Disadvantages of IaaS

IaaS provides a number of distinct advantages:

  • High degree of control – The cloud provider is responsible for hardware, but beyond that, the cloud user can configure the compute resources in any desired manner. If compute resource was created for a website, all aspects of it can be configured – this is great for systems that may require 3rd party software that’s difficult to support under PaaS.
  • Automation – IaaS can usually be configured using lots of different forms of tooling. Writing Infrastructure-As-Code is a great way to quickly and reliably provision resources.

IaaS also has some very notable disadvantages:

  • Security vulnerabilities – As the cloud user is responsible for patching, resources may have more security vulnerabilities.
  • Higher administrative overhead – As more responsibility falls on the cloud user, more administrative functions need to be used.
  • Complexity – IaaS may require additional training/knowledge to fully support the IaaS cloud infrastructure.

What is PaaS (Platform as a Service)?

This model represents a managed hosting environment. The provider manages the virtual machines and networking resources – but the user is responsible for deploying their applications into the environment. A website hosted in Azure App Service is an example where a user would upload their web application, but without worrying about physical hardware and software requirements and all the middleware that would make the website work.

PaaS focuses on application development.

Advantages and Disadvantages of PaaS

PaaS provides a number of advantages:

  • Low administrative overhead – As PaaS includes all of the infrastructures, there is a lower administrative overhead. The cloud provider maintains the security and patching of the underlying infrastructure.
  • Flexibility – PaaS provides a great platform to allow developers to develop an application whilst the cloud provider manages all the infrastructure and middleware.

PaaS does have some disadvantages:

  • Migration – Migrating away from a cloud provider can be more challenging. As the application development may be tailored to a specific provider (Such as AWS or Azure) – Switching provider is far more complex.
  • Data security – As data is stored outside of the cloud user’s control. A deeper understanding of how it’s stored is required. Ensuring that access and protection meet the cloud user’s requirements and perhaps any legal requirements.

What is SaaS (Software as a Service)?

The cloud provider manages all aspects of the environment such as virtual machines, networking, data, and applications. The user only needs to provide data to the managed application. Office 365 is an excellent example of SaaS.

SaaS is the most used of the three models, with most businesses using huge SaaS platforms such as Salesforce, Dropbox, Zoom, HubSpot and even Office 365

Advantages and Disadvantages of SaaS

SaaS provides advantages such as:

  • Cost – SaaS is a great pay as you go model, there can be large cost savings – and flexible methods of payment. For example, Microsoft offers different plans that include different things in their Office 365 plans allowing you to pay only for the services you need.
  • Ease of use – Not being concerned about the infrastructure, application, networking, etc. of a SaaS solution is a very clear advantage. Once you’ve paid for the software and installed it, you’re ready to go.

SaaS does have some disadvantages:

  • SLA response time – Whilst your IT MSP will likely have an agreed SLA response time of a few hours, SaaS providers have response times of up to a few days, or more. This becomes a big issue when trying to get your staff back up and running in the event of a business-wide outage.
  • Data security – You are reliant on the cloud providers security measures. Big companies such as Microsoft will have great security in place but they’re also bigger targets. If the system becomes compromised, it leaves your sensitive business data at risk.

How can Tribeca help?

Which model you need will depend on the objective of your business. For example, if you’re looking to standardise the software your staff are using with the ability to centrally manage licenses, a SaaS solution is what you need. If you’re beginning to develop your own software but don’t want the hassle of managing the hardware and middleware, then PaaS is the model for you. Or, if you need an underlying infrastructure but don’t want the hassle of purchasing and installing the hardware yourself then IaaS is the way to go. The reality is most businesses will use a mix of all three models within their IT Infrastructure.

Tribeca is experienced in using all three models and can advise you on the best ways the utilise them all in the best way possible. We can provide pricing, configure the platforms and also continue to support and maintain the solutions for you.

Tribeca also offers IT support services tailored to businesses in the Alternative Investment sector. From Hedge Fund IT Support to Private Equity IT Support. We operate as your business partner and want to be seen as an extension of your business, providing consistent quality and proactive assistance to help you grow and protect your business. 

For more information on our IT support and managed services for the alternative investment sector, get in touch with us today.


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