Infrastructure as a Service (IaaS) is a cloud delivery model that provides on-demand computing resources over the internet, including networking, storage, and other infrastructural components. IaaS allows users to develop, grow, and scale without buying and maintaining physical hardware. The power and flexibility of IaaS enable it to support a wide variety of businesses, developers, researchers, and other individuals who want control over their infrastructure and the software inside that infrastructure.
Before IaaS, businesses would have to purchase and maintain their hardware and software for their computing needs. This was expensive to implement, with a high purchase cost of the hardware, and costly to maintain, requiring individuals with technical expertise to dedicate significant amounts of time to the upkeep of the physical infrastructure. Scaling apps was also difficult because companies were often constrained by the capacity of their on-premise infrastructure. IaaS helps lower IT costs significantly, allowing organizations to reallocate that money to development. It’s also flexible enough to allow businesses to scale, promoting rapid growth alongside financial savings.
There are several delivery models for cloud computing, typically done through Infrastructure as a Service (IaaS), Platform as a Service (PaaS), or Software as a Service (SaaS). There are fundamental differences to each delivery model and pros and cons for each depending on the user’s needs.
With IaaS, users can choose the level of control they have over their infrastructure, but they don’t have to control or manage the physical hardware. Developers can set up their infrastructure and decide what layers of abstraction they want. To make maintaining their application easier, they can layer in things like load balancers or even managed services like Managed Kubernetes or Managed Databases.
With PaaS, users no longer have to manage the operating system, runtime, or other infrastructural components of their application. PaaS is great for developers who don’t need to customize their underlying infrastructure, as it provides a fully managed solution. When a developer chooses to use PaaS, all they have to consider is their code. They can focus on the development work they are trying to do and let the provider manage backend services and system administration. Once they upload their code and their application is live, their job is done. PaaS products are very powerful and make it easier to scale, rapidly iterate, and quickly deploy.
SaaS is a software delivery model in which a third-party vendor provides the software application over the internet. SaaS applications are typically built inside cloud infrastructures and can be accessed from anywhere with an internet connection. With SaaS, users have access to software provided by third-party vendors but are not in charge of the production, maintenance, or modification of that software. Users are only exposed to the interface they interact with.
IaaS is broken into three main components: compute, network, and storage. With these offerings, users have the building blocks they need to create their customized systems, as complicated or powerful as they need, and the ability to scale up and down based on current needs.
Foundational IaaS computing resources begin with servers. Servers are powerful computers that tend to have hundreds of Central Processing Units (CPUs), hundreds or thousands of gigabytes (GBs) of Random-access memory (RAM), and thousands of GBs of storage. Servers are expensive to buy and costly and difficult to maintain. IaaS providers maintain datacenters that house the physical, bare-metal servers. These physical servers can be partitioned using a hypervisor into smaller “virtual machines”. These virtual machines can run their OS and applications independently while sourcing power from the bare-metal server.
There are different ways to set up a virtual machine (VM), and the architecture you choose will depend on your needs and the level of abstraction you prefer. For example, developers can
Use Kubernetes to containerize their code so that namespaces, which are like smaller, lighter VMs, serve only one purpose, like running an application. Kubernetes then orchestrate or manage those containers for the developer, managing traffic and automatically scaling the application up and down as needed. Compute offerings often include optional add-ons like load balancing, which automatically distributes network traffic to prevent system overload.
When users purchase a virtual machine through an IaaS provider, they choose the operating system, often referred to as an image, and applications run on that machine. Developers can easily scale vertically by adding more CPU if their VMs don’t have enough processing power or scaling horizontally to increase instances and handle more load. Virtual machines can often be quick and easy to set up.
Storage options are threefold: file storage, object storage, and block storage.
File storage is similar to what we have on our computers at home and stores data as a single entity into a file. The files can exist within each other as other data, so it’s hierarchical. For example, a path for file storage could be “/home/photos/selfie.jpg”. Object storage instead takes saved data as a single entity and appends metadata and an identifier. Object storage deals with whole objects stored over the network. These objects could be things like an image file, logs, or HTML files. Object storage is the most popular option because of its simplicity and cost savings. Block storage is likely underneath the file or object storage. Block storage services are relatively familiar. They provide access to a traditional block storage device over the network and attach it to your virtual machine. It takes data and saves it as blocks of actual bytes or bits. It has advantages over the other two by being faster to transfer data but not user friendly unless abstracted by a file system like in your computer that uses it.
The network function talks to the storage function, other VMs, containers, other servers, the internet, the intranet, and other components. It’s how information is transferred through the architecture regardless of endpoints. Users will need different networking bandwidths depending on the amount of data transmitted between computing resources.
Iaas is a popular option for all kinds of businesses, especially new businesses, because it allows them to scale up and down as needed and avoid the hassle and cost of maintaining servers themselves.
There are several advantages to IaaS: