The term Hardware as a Service (HaaS) refers to two very separate ideas, both of which involve paying for hardware on a subscription model but are otherwise unrelated. The term, used in the areas of managed services and grid computing, piggybacks off other "as a service" concepts, especially the Software as a Service (SaaS) model popularized largely by Salesforce.com.
HaaS in managed services
For managed service providers (MSPs), HaaS is a financing model almost identical to leasing. The hardware to be managed is placed at the client's site, and its cost is built into the monthly subscription rate that the user pays for the managed service.
The MSP business model centers around the service provider remotely monitoring and controlling a client's on-site hardware and software. This gives the customer many of the benefits of an on-premise system without the need to maintain a corresponding IT staff, and because most of the management work is done remotely, MSPs save time and money that would otherwise be spent traveling to client sites. But MSPs have to be familiar with the hardware they monitor, and the hardware itself must be able to be remotely monitored and managed by the MSP, which sometimes means installing new hardware if a client's existing system can't be controlled remotely.
Traditionally, MSPs would provide that hardware, and its cost would simply be a part of the monthly fee, said Oli Thordarson, CEO of Alvaka Networks, an MSP in Irvine, Calif. But as smaller companies started providing managed services, they found that they could not afford the up-front costs for the hardware, he said. The solution was to lease the hardware directly to the client, so that the client would provide the credit and financial responsibility for it instead of the MSP -- a model called Hardware as a Service.
The old model, under which MSPs provide the hardware and build its cost into the monthly subscription fee, can also sometimes be referred to as HaaS.HaaS as grid computing
Hardware as a Service is also a term coined by Nicholas Carr, author of "Does IT Matter?," to describe a form of grid computing in which customers pay for usage of a provider's grid on an as-needed basis. A number of companies provide this service, such as Amazon.com with its Elastic Compute Cloud (EC2) service.
With this form of HaaS, a customer sends data to the provider along with instructions on how it should be processed, and the HaaS provider's computers provide the actual computation power. With recent developments in the field, customers are able to choose the operating system used on the back end or even create a virtualized server to run the computation on.
This form of HaaS is similar to the more well-known Software as a Service concept in that it provides access to a provider's IT infrastructure through the Internet. But whereas SaaS providers sell access to their software -- the hardware it runs on is incidental for the end user -- HaaS sells access to the hardware itself, and the software that's run on it is the responsibility of the customer.
Carr said Hardware as a Service, which he sees as part of the increasing commoditization of IT, is currently used by small and sometimes medium-sized businesses to gain access to sophisticated infrastructure without having to build it themselves. But he said larger companies are also starting to look into it, so they can handle spikes in demand without needing to buy hardware that goes unused most of the time.