What is IaaS?
IaaS is one of the many cloud service models that have the words “as a service” (abbreviated “aaS”) as part of their names – software as a service (SaaS), platform as a service (PaaS), network as a service (NaaS) and so on. (It may also be called hardware as a service [HaaS].) The infrastructure modifier refers to the development tools in a computer system – the database management system (DBS), the communications protocol, the operating system, the compilers and so on – a definition which thus excludes applications. More specifically, IaaS is “a provision model in which an organization outsources the equipment used to support operations, including storage, hardware, servers and networking components.” This article will describe what any cloud user should know about IaaS from ProfitBricks – what it consists of, what purposes it serves and how to run it.
IaaS as a cloud platform
First, let us consider where IaaS stands in the larger context of the cloud. It is the most basic of all the cloud models: If they are arranged in a hierarchy according to their complexity, IaaS is on the very bottom, with PaaS on the level above it and SaaS on the one above that. Each of these is abstracted from the details of the one below it.
IaaS provides all the foundational tools required for development as an alternative to the traditional infrastructure setup. Traditionally, developers would require space in a data center (typically leased), as well as real estate, labor, hardware, racks and the utilities needed to maintain cloud servers and data storage. IaaS is therefore a simpler and more affordable option; users simply rent space in a virtual, existing data center from the IaaS provider.
The traditional steps can take weeks to months to configure, whereas a user can be up and running with an IaaS platform much more rapidly – sometimes within minutes, as the consumer is simply tapping into an existing configuration rather than starting from scratch.
Characteristics of IaaS
As mentioned in the first section, IaaS provides the networking, storage, virtualization and other items that together make up the infrastructure of a cloud network. The tasks involved in the administration are mostly automated. IaaS is also characterized by dynamic scaling – a form of display in which the size of the window determines the scaling factors, for instance when an image is scaled to fit the width of the display.
Each cloud platform has its own consumer, type of service provided by the cloud, service level coverage and form of customization. In the case of IaaS, the consumer is the owner of the application. The service provides a virtual server and cloud storage. Service level coverage includes virtual server ability and time to provision but excludes application and platform coverage. Only a minimal amount of constraints is installed on a standardized virtual operating system build.
Desktop virtualization is another characteristic of IaaS. The desktop environment, and all the application software associated with it, are separated from the physical device whereby they are accessed. Sometimes there may be API (application programming interface) access to the infrastructure. An API specifies the forms of interactions among the components of a software program.
Here are some more characteristics of IaaS:
- The computing resources of the provider, including storage, memory and bandwidth, are pooled so that any number of consumers may be served.
- It is a measured service. This means that it is possible for both the provider and the consumer to measure the amount of memory or bandwidth that is being used.
- The capabilities can be rapidly provisioned and released to scale out and can be accessed over the whole Internet. The consumer can buy any amount of capabilities at any time.
- Users have complete control over the virtual data center architecture, allowing the user to design and deploy cloud servers, networks and storage in minutes.
- Both utilization and expenses are scalable and elastic. Users have on-demand access to additional storage and bandwidth, enabling seamless growth and eliminating resource waste. Some IaaS providers enable automatic performance adjustments to accommodate the present workload, providing an ideal service for companies with constantly changing resource demands.
How the expenses are paid
Services that are fully outsourced can be purchased by the client, in which case the amount of the resources that they use determines how they are billed. The cloud provider installs the virtual server on the client’s IT infrastructure for a rental fee. IaaS is billed according to the “utility computing model,” whereby the use of the service is treated as if it were a utility, much like electricity or water services.
With a traditional data center configuration, the user pays for the full space rented, the full cost of real estate, utilities, hardware, racks and the other costs described above that are required for a traditional setup. Even if only a portion of the full server and storage capacity is being utilized, the consumer pays as though it’s being used at full capacity. The IaaS consumer, on the other hand, pays only for the services actually used in each billing cycle, such as CPU cores, storage, data transfer or RAM. By distributing the costs of maintaining a data center across multiple consumers sharing a set of resources, consumers pay a lower cost with IaaS while reaping the full benefits of a virtualized data center.
Management of the infrastructure components and the server itself is the province of the seller; however, the client is still responsible for data and applications, as well as for “middleware,” programs that provide software applications with services that are not included in the operating system. Depending on the type of infrastructure they choose, he or she can install any platform that is needed.
The IaaS provider is responsible for maintaining the hardware, networks and virtualization layer, while the consumer maintains his own software, operating system, and their own virtual data centers and networks. With IaaS serving as the foundation for developers to create and deploy their own applications, it makes sense for the consumer to retain more control and handle maintenance of these components, as there is no limit to the number of custom applications that could be running on an IaaS platform at any time.
Types of clouds
The user should also know that there are three types of clouds: Public IaaS Cloud, Private IaaS Cloud and Hybrid IaaS Cloud.
With the Public IaaS Cloud, users share server resources with other consumers. This model is the simplest to implement and offers the greatest scalability of any of the cloud models, enabling the consumer to pay only for the resources utilized – so the cost for services can vary from month to month (or whatever billing cycle is used) based on actual consumption.
In the Private IaaS Cloud model, virtualization technology is used to provide cloud computing services privately to a single organization. The cloud service, in this instance, is maintained by the consumer and is positioned behind the company’s firewalls for maximum security. The servers are used exclusively by the consumer. This model is best suited for companies who already have their own database and security professionals to adequately maintain the system.
The Hybrid IaaS Cloud can use either public or private servers. In this case, the consumer may run some servers privately while outsourcing others to the public cloud for scalability. This option is ideal for companies who require the flexibility of the cloud but also have servers that aren’t suitable for that model or contain sensitive information best maintained in a private server.
Who should be using IaaS?
Iaas is used by a variety of enterprises, startups, small-to-medium businesses (SMBs) and even independent software vendors. Deploying and maintaining a SaaS platform on an IaaS platform, for instance, is not only possible but ideal for SaaS providers. The scalability and elasticity of IaaS means it’s a viable solution for practically any company with database and server requirements. With significantly lower costs than maintaining a traditional data center, IaaS is simply the most logical solution.
