📖 What is Infrastructure as a Service (IaaS)?
Infrastructure as a Service (IaaS) is a cloud computing model that provides virtualized computing resources, such as servers, storage, and networking, over the internet. Users are responsible for managing the operating system, middleware, and applications installed on the infrastructure.
"IaaS gives the most control. If you are renting a 'blank' virtual machine in the cloud, you are using IaaS."
📚 Certification: CompTIA A+ Certification Exam Core 1 (220-1101)
🔑 What are the Key Concepts of Infrastructure as a Service (IaaS)?
- ▸ Shared Responsibility Model: The provider manages the physical hardware and virtualization layer, while the user manages the OS, applications, and data security.
- ▸ Scalability and Elasticity: Users can rapidly increase or decrease computing resources like CPU and RAM based on current demand to optimize costs.
- ▸ Virtualization Foundation: IaaS utilizes hypervisors to create virtual machines, allowing multiple isolated server instances to run on a single piece of physical hardware.
- ▸ Administrative Control: This model provides the highest level of control, granting users root or administrator access to the virtual server's operating system.
- ▸ Resource Provisioning: Users can specify exact hardware requirements for their instances, mirroring the experience of deploying a physical server in a local datacenter.
🎯 How does Infrastructure as a Service (IaaS) appear on the 220-1101 Exam?
You may be asked to identify the cloud model for a company that wants to migrate legacy server images to the cloud while maintaining full control over the OS.
A scenario might describe a technician needing to deploy a custom Linux distribution with specific kernel tweaks; expect to select IaaS as the only model providing this access.
Expect questions where you must distinguish between IaaS, PaaS, and SaaS based on who is responsible for patching the operating system and managing the virtual hardware.
❓ Frequently Asked Questions
Why would a company choose IaaS over a simpler model like SaaS?
IaaS is chosen when a company needs complete control over the software stack, custom configurations, or specific OS versions that are not available in pre-packaged software services.
Who is responsible for security updates in an IaaS environment?
The cloud provider secures the physical data center and hypervisor, but the user is responsible for updating the guest OS, installing antivirus, and patching all installed applications.