This is a question many businesses are faced with as they consider the migration to cloud services. The main difference between these three solutions are what they offer to end users right out of the box, so to speak. Before even thinking about which solution is the right one for you it's beneficial to spend some time understanding what each of them are, what benefits they bring to the table, and when you should consider them for your own business needs.

IaaS

Infrastructure as a Service (IaaS) is a type of cloud computing that provides users with computing resources over the internet. With IaaS solutions, the responsibility of maintaining equipment falls solely on the shoulders of the cloud service provider. In the event there are any technical issues or outages, the end user must contact the provider who then undertakes corrective action spending on the Service Level Agreement. IaaS solutions eliminate the need for users to procure and maintain their own hardware in datacenters. This is ideal for clients looking for a way around the expenses associated with the upkeep of equipment in a datacenter, while still maintaining nearly the same level of control that they would have in a colocation environment.

Pros

IaaS solutions are typically advertised by providers with one of the following buying options: pay-as-you-go or subscription. With the pay-as-you-go model, you are charged by the provider based on the amount of computing resources that you consume based on a per hour or per day rate. The rate in which you are measured varies by provider. On the flip side, utilizing the subscription model, users are charged a fixed monthly or yearly rate regardless of the amount of resources they end up consuming. Having multiple ways of budgeting out your IaaS needs is an appealing draw of this solutions.

Cons

In 2017, several massive companies with millions of users experienced lengthy outages. Netflix, Reddit, Pintrest, Tinder, Dropbox, and thousands of other websites were down for 4 hours. This lead many people to speculate that the entire internet was down. The issue wasn’t the entire internet but rather an Amazon Web Service outage which resulted in many big name websites suddenly becoming inaccessible. In that year, AWS accounted for over 49.4% of the total IaaS market share. The reason for their stranglehold on the industry is because they were the first to get IaaS solutions on the market but now there are many other providers which offer similar services. However, this outage highlights one of the concerns with IaaS solutions: while they offer reduced up front costs, on demand scaling, and flexibility, they also come with disadvantages like reduced independence and occasional downtime issues.

When To Use It

Anyone looking to avoid spending time and money on purchasing hardware or creating software should consider IaaS. In particular, companies that are experiencing massive growth should look into IaaS solutions as the scalability is seemingly endless and you can change out hardware and software as your clients' needs evolve. 

Examples

• AWS

• Azure

• Google Compute Engine

• Linode 

PaaS

Platform as a Service (PaaS) can be viewed as a toolbox filled with cloud based services which allow developers to create applications. The benefit to building in the cloud versus on-premise in a datacenter is that building in the cloud allows developers to create at a speed unmatched by any on-prem solutions. Since the services are provisioned over the internet, there’s no need to worry about setting up and maintaining servers, patching, upgrading, or authenticating. This gives time back to developers, allowing them to focus resources on creating the best user experience possible for their application. 

Pros

PaaS solutions offer a wide array of services including workflow and design tools and rich API’s. This allows developers to build applications with the click of a button and pre-set lines of code as opposed to worrying about infrastructure and operating systems. This ease of use is what draws many companies looking to create and go live with an application quickly. Development tools, servers, and programming environments are all ready for use, via the cloud, without the complexity that’s required to create them in house, saving both time and money. With very low start up costs developers are able to create and host applications without a lot of the delay that are typically caused by infrastructure issues. Developers can product high quality results at a much faster clip.

Cons

With PaaS solutions is that data residing in third party, vendor controlled cloud services may pose a security risk and your security options may be limited due to specific hosting policies set forth by your vendor. Also, PaaS solutions may not be optimized for the language and framework of your preference.

When to Use It 

When you have multiple developers working on different projects at the same time, PaaS solutions can be beneficial because they are capable of streamlining workflows. PaaS is also especially useful to organizations that need to create customized applications as the speed and flexibility with which you can create is immense. Overall, this cloud service can save time and money by simplifying many of the challenges that come up when you’re rapidly developing and hosting applications. 

Examples

• Heroku 

• OpenShift 

• Force.com 

SaaS

Software as a Service (SaaS) is one of the most widely known and commonly used business solutions in the cloud market. SaaS solutions utilize the internet to deliver applications, which are run entirely by third party vendors, to their end users. The vast majority of applications delivered via SaaS are run completely through the end users web browser, which eliminates the need for downloads or installation of new software for a potential client. This means that any technical issues related to data, servers, or storage are managed by the vendor providing the SaaS solution. 

Pros 

The amount of time and money saved on projects like installing, managing, and upgrading software are one of the main reasons why companies are drawn to SaaS solutions. This allows the technical staff within an organization to focus to focus on other essential tasks. SaaS solutions are managed from a central location so in addition to reducing the costs associated with maninting infrastructure, they also streamline the maintenance and support available for businesses as there is one main point of contact for all technical issues. 

Cons

There are some potential drawbacks that companies considering SaaS solutions should consider. SasS vendors typically make it very easy to join a service but very difficult to get out of it. Vendor lock-in should be considered at the beginning stages of looking into a SaaS solution so that you’re not stuck with a service that doesn’t provide what you need. For instance, not every vendor follows standard APIs, protocols, and tools, yet those features could be essential for your business. It’s essential to consult with an expert to make sure you’re getting what you need out of a potential vendor. 

When to Use it

Startups or smaller companies looking to save money up front would benefit from a SaaS solution. Not having to worry about server issues or software is appealing for many organizations. Also, anyone looking to get a short term project up and running quickly and affordably would benefit from going the SaaS route. Any application that requires both web and mobile access are ideal for SaaS as well. 

Examples

• DropBox

• SalesForce 

• GoToMeeting

• Cisco WebEx