Explaining the Cloud Models: A Guide to IaaS, PaaS, and SaaS

The cloud has transformed how organizations access computing resources and applications. But with so many options for cloud models like IaaS, PaaS, and SaaS, it can be confusing to know where to begin. This article will clearly explain the major cloud service models so you can determine the right approach for your business.

IaaS Cloud Model: Flexible Infrastructure Without Maintenance

Infrastructure-as-a-Service provides the foundation of the cloud – the servers, storage, networking, and data centers. With IaaS, you essentially rent this infrastructure from a cloud provider like Amazon Web Services, Microsoft Azure, or Google Cloud Platform.

The two primary benefits of IaaS are:

• Flexibility - Scale infrastructure up or down based on demand, without having to maintain it yourself. This allows you to adjust capacity on the fly to meet spikes or lulls in usage.
• Cost savings - Only pay for the infrastructure you use. This converts capital expenditures to operating expenses, so you avoid large upfront investments. And you can scale back during quiet periods to reduce costs.

However, with IaaS, your IT team still manages the following:

• Operating systems
• Middleware
• Runtimes
• Data
• Applications

So, IaaS requires more technical expertise than other cloud models. Your admins still handle patch management, configuration, and security measures. You have more control over the technology stack, but also more responsibility.

Some key use cases for IaaS include:

• Setting up development and test environments - Quickly spin up infrastructure as needed for developers, QA, and testing. Tear it down when a project ends.
• Disaster recovery - Replicate your mission-critical infrastructure to the cloud so you can fail over seamlessly in an emergency.
• Storage and backups - Take advantage of cloud storage for capacity, durability, and geographic replication.
• Web hosting - Launch web servers in the cloud to support traffic spikes driven by campaigns or seasonal usage.
• High-performance computing - Access cloud-based supercomputing capabilities for data analysis, scientific modeling, and machine learning.

IaaS offers flexible access to enterprise-class data centers and hardware without the overhead of managing your own infrastructure. For workloads that require broader control over the environment, IaaS is an ideal choice.

PaaS: A Cloud Model for Developers

Platform-as-a-Service provides a complete development and deployment environment in the cloud. The cloud modelr manages the following:

• Infrastructure (servers, networking, storage)
• Middleware (databases, security, integration)

While you build the applications on top.

This greatly simplifies and accelerates application development by providing baked-in services like:

• Database management
• User authentication
• Messaging queues
• Caching
• And many more

Developers can easily collaborate with built-in tools for:

• Source control
• Code sharing
• Code review
• Release management
• Dependency management

Since the provider handles infrastructure, middleware, runtimes, and ops, you can focus your development resources on writing amazing code. PaaS speeds up development cycles and is ideal for agile, iterative software methodologies.

Some examples of PaaS providers include Heroku, AWS Elastic Beanstalk, Microsoft Azure App Service, Salesforce Platform, and Red Hat OpenShift.

Benefits of PaaS cloud model include:

• Increased developer productivity - Developers spend more time coding vs. configuring infrastructure.
• Faster time-to-market - Streamlined deployment and operations accelerate launch.
• Built-in scalability - Apps can scale up seamlessly to meet demand without rearchitecting.
• Consistent environments - Standard tooling and runtimes across dev, test, and production environments.
• Operational efficiency - No need to manage servers, updates, or patches.

PaaS is optimal for cloud-native and mobile applications that leverage APIs, microservices, and modern app architectures. It reduces the burden on IT while giving developers ready access to everything they need in a single platform.

SaaS: Instant Productivity for End Users

Software-as-a-Service provides complete software applications over the Internet. This model allows users to instantly access software without any installation or management.

Common examples of SaaS applications include:

• Email (Gmail, Office 365, Outlook.com)
• Collaboration tools (Slack, Dropbox, Box)
• CRM (Salesforce, Zoho)
• HR systems (Workday, BambooHR)
• Finance/accounting (NetSuite, Quickbooks)
• And countless more across all industries

End users can access SaaS apps from any device with an internet connection. This enables productivity from anywhere - at the office, at home, or on the go.

The SaaS provider handles all aspects of the application:

• Infrastructure
• Middleware
• App code
• Data storage
• Security patches and upgrades

This offers the fastest time-to-value over other cloud models. If you have a business need that can be met by an off-the-shelf SaaS product, it can typically be deployed right away with minimal configuration.

Some benefits of SaaS:

• Rapid deployment - Get started in days or weeks vs. months.
• Pay-as-you-go pricing - No large upfront costs for licenses or hardware.
• Automatic updates - New features and fixes rolled out seamlessly.
• Mobile access - Use apps on iOS, Android, Windows Phone, and tablets.
• Collaboration - Many SaaS apps integrate with each other for workflow.

For commonly used applications like email, calendaring, and office productivity, SaaS delivers instant usability with minimal IT management.

Of course, SaaS applications are also available for specialized business functions like ERP, marketing automation, billing, expense reporting, and much more. Enterprises can leverage SaaS for these needs while focusing internal development on proprietary apps that differentiate their business.

Choosing the Right Cloud Model

When determining the best cloud approach, consider factors like:

• IT resources and technical expertise - IaaS requires experienced sysadmins, while SaaS needs little IT involvement.
• Security and compliance requirements - IaaS offers more control, while SaaS relies on the vendor.
• Budget - IaaS and PaaS offer adjustable spending, and SaaS is pay-as-you-go.
• Application requirements - Existing apps may need IaaS or PaaS, while many needs can be met by SaaS apps.
• In-house vs. external development - PaaS accelerates new development, while SaaS provides off-the-shelf apps.
• Timeframe - SaaS can be up and running in days or weeks.

Here are some guidelines for choosing the right cloud model:

• IaaS - Existing or legacy apps, full control over the environment, advanced IT skills
• PaaS - Building cloud-native apps, focus on speed of development
• SaaS - Simple collaboration and productivity, rapid deployment, ease-of-use

In most cases, a hybrid model delivers the greatest flexibility. Here are some examples:

• Use SaaS for messaging, office productivity, HR, marketing, and collaboration tools.
• Leverage PaaS for rapid development and deployment of customer-facing web and mobile apps.
• Keep legacy systems and databases running via IaaS virtual machines.
• Extend legacy apps by building new microservices on PaaS that integrate via APIs.
• Manage sensitive systems on private IaaS internally while leveraging public IaaS for web servers, storage, and backup.

Blending the strengths of multiple models allows you to be nimble. Take advantage of cloud innovations while maximizing your existing systems.

Conclusion

IaaS, PaaS, and SaaS provide varying levels of capability and control in the cloud. IaaS offers flexible infrastructure and hardware without maintenance overhead. PaaS provides a complete platform to accelerate software development and deployment. SaaS delivers instant usability for end users with minimal configuration.

Evaluating their differences allows you to take advantage of the benefits of each. You can balance factors like agility, security, capability, and cost to create an ideal cloud environment tailored to your enterprise needs. With a mix of private and public resources, plus Intel innovation across the stack, you can build a robust hybrid cloud model that powers your organization now and into the future.