With increasing interest in cloud computing services globally, where applications and software are made available on pay-per-use model, Indian IT firms, too, are expected to join the bandwagon in a big way over the next 2-3 years, says research firm Ernst & Young (E&Y).

Cloud computing refers to a pay-per-use model, where applications and software are accessed over Internet and not owned by users. It has three parts: software-as-a-service (SaaS), platform as a service (PaaS) and infrastructure as a service (IaaS).

In a survey by E&Y titled 'Cloud adoption in India - Infrastructure as a Service (IaaS)', over 72 per cent of the Indian IT infrastructure firms surveyed said they will adopt cloud computing in a big way over the next 2-3 years.

IaaS means companies, instead of purchasing servers or data center space, outsource these services from vendors.

"We have seen significant interest in the potential of IaaS for the Indian market across industry segments.

virtualisation, often seen as the first step, has begun to be more widely implemented across data centers," E&Y Partner (Technology Advisory Practice) Milan Sheth said.

E&Y surveyed 50 chief information officers (CIOs) from leading small and medium business, enterprises and IaaS firms.

About 92 per cent of the India CIOs surveyed were inclined to buy cloud services from data center service providers and IT systems integrators.

Indian cloud computing market is expected to touch USD 1.08 billion by 2015, from the current USD 110 million, according to a consulting firm Zinnov.

The adoption would be driven as companies can move to an operating expenditure from a capital intensive model, deploy solutions faster and focus on core competencies rather than IT requirements.

Interestingly, cost is not the decision factor when it comes to adoption of cloud IaaS.

"With high awareness levels and the positive perception of cloud indicate a market that will see robust growth rate in the next two years," Sheth said.

However, lack of ecosystem maturity, customer awareness of services and connectivity would be major challenges for adoption of cloud IaaS in India, the study said.

Also, security of data remains a concern for the companies since the data is not hosted on their own servers.

About 72 per cent of the respondents cited data privacy and security issues as a concern area for their business while adopting cloud computing services.