Infrastructure as a Service (IaaS) is a cloud model which allows organizations to outsource computing equipment and resources such as servers, storage, networking as well as services, such as load balancing and content delivery networks. The IaaS provider owns and maintains the equipment while the organization rents out the specific services it needs, usually on a "pay as you go" basis. Today, the question is less about whether or not to use IaaS services, but rather which providers to use.
It's easy to think of IaaS as a commodity product, that all virtual machines are essentially the same regardless of where they reside. There is some truth in that, however the distinguishing features of each cloud provider, especially around management and specialized services, are what's important to administrators. When evaluating IaaS providers, it's important to look beyond the range of cloud services that are offered and consider management functions, monitoring tools, identity management, service level agreements and customer support.
We help you get started by summarizing these key considerations of several IaaS providers. Although this is not a comprehensive list, the vendors represent a sample of the major IaaS offerings that are available today. As you'll notice, some vendors focus on helping you integrate public cloud services with your existing infrastructure creating a hybrid environment. And many offer a free trial so you can see if their services and management platforms are right for your organization's needs.
Amazon Web Services offers a full range of compute and storage offerings, including on-demand instances and specialized services such as Amazon Elastic Map Reduce (EMR) and Cluster GPU instances, as well as Elastic Block Storage (EBS) and high performance SSDs on the storage side. Additionally, the IaaS offers infrastructure services such as workflows, message passing, archival storage, in-memory caching services, search services, both relational and NoSQL databases and more.
|Key Features||Rich set of services and integrated monitoring tools; competitive pricing model.|
AWS can also be used as a PaaS.
|Limitations||AWS is a complex mixture of services. As your workflows become more complex and you use more services it can be difficult to project expenses. However, Amazon offers a monthly calculator to help estimate your costs.|
|Pricing||Instances range from $0.113/hour to $6.82/hour, with volume discounts available for reserved instances. Storage prices range from $0.095/GB/month to $0.125/GB/month. Additional charges for application services and data egress may apply. |
|Bonus||New users can get 750 hours, 30GB storage and 15GB bandwidth for free with AWS's Free Usage Tier.|
Despite the name, Windows Azure is not a Windows-only IaaS. The compute and storage services offered are typical of what you'll find in other IaaS providers, and administrators used to Microsoft platforms will find working with Windows Azure much easier. The IaaS offers ready access to virtual networks, service buses, message queues, and non-relational storage platforms as well.
|Key Features||Easy-to-use administration tool, especially for Windows admins. Windows Azure can also be used as a PaaS.|
|Limitations||Minimal, easy-to-use portal interface may not be so appealing to command line gurus.|
|Pricing||m $0.02 to $1.60 per hour. Storage prices range from $0.07/GB/month to $0.12/GB/month, depending on level of redundancy.|
|Bonus||Free 30-day trial with a limit of up to $200 is available for new users.|
Google Compute Engine is well suited for big data, data warehousing, high performance computing and other analytics-focused applications. It is well integrated with other Google services, such as Google Cloud Storage, Google BigQeury and Google Cloud SQL. Although Google Compute Engine is still relatively new in the IaaS market, the fact that it runs on Google's global infrastructure, including the company's private global fiber network and high efficiency data centers sets it apart.
|Key Features||With the Google infrastructure backing it up, this IaaS is designed to scale.|
|Limitations||Lacks ease of administration features. Running Hadoop on Google Compute Engine, for example, requires more from users; because it's not integrated you have to download the Hadoop package, a patch for Hadoop and a set of JDK packages along with several other steps (outlined here) to deploy a Hadoop cluster.|
|Pricing||Instances range from $0.019/hour to $1.659/hour. Provisioned storage is $0.04/GB/month; snapshot storage is $0.125/GB/month.|
|Bonus||Google charges by the minute after a minimum of 10 minutes in an hour.|
Rackspace offers core cloud computing services with a strong focus on customer service. Rackspace is one of the co-founders of OpenStack, which it uses for its cloud infrastructure, so you can run the same platform in-house if you decide to move to a private or hybrid cloud down the road. You can choose from a variety of operating systems, including Linux and Windows Server. And for an extra fee, you can easily create basic monitoring checks, like ping or HTTP checks.
|Key Features||Easy to use control panel, especially for non-system administrators, and strong customer service.|
|Limitations||No messaging or specialized services (like Amazon Simple Queue Service and DynamoDB), although there are alternatives (like RabbitMQ and MongoDB or CouchDB) that you can run, you'll just need to manage them yourself.|
|Pricing||Instances start at $0.04/hour and go up to $5.44/hour. File storage starts at $0.10/GB/month and block storage is $0.12/GB/month.|
|Bonus||Rackspace is currently offering a $100 credit on your first month bill.|
IBM SmartCloud Enterprise offers core compute and storage services in a 5-tier model along with an asset catalog of IBM and non-IBM software. The IaaS is ideal for enterprises managing a large number of developers and testers who need to deploy virtual machines and allocate storage as efficiently as possible. You can manage administrator and user roles, set limits on resources users can deploy and readily report on user activity.
|Key Features||A good combination of management, software and security features for enterprise cloud administrators.|
|Limitations||May find difficulty distinguishing itself from other OpenStack providers, at least among non-IBM customers.|
|Pricing||Hourly and monthly pricing available, however numbers are not disclosed. Contact IBM for details.|
|Bonus||Free cloud server for one month from IBM's SoftLayer.|
HP's cloud is built on OpenStack and its IaaS service is part of the company's Converged Cloud Solutions for public, hybrid and private clouds. HP offers Windows and Linux command line interfaces in addition to the dashboard as well as a RESTful API so you can use cURL for low level access to HP's cloud functions. HP cloud also offers simple access to its content distribution network (CDN), particularly useful for companies with a global customer and/or user base.
|Key Features||A good solution for enterprises wanting to integrate their existing IT infrastructure with public cloud services and investing in a hybrid cloud.|
|Limitations||HP is still relatively new in the IaaS space with a limited track record and feature set compared to more seasoned providers. |
|Pricing||Instances range from $0.03/hour to $3.40/hour. Block storage is $0.10/GB/month while object storage costs $0.09/GB/month.|
|Bonus||Free 90-day trial with a $100 credit for each of your first three HP Public Cloud monthly invoices.|