Vendor revenue from sales of infrastructure products (server, storage and Ethernet switch) for cloud IT, including public and private cloud, grew 21.9% year-over-year to $29 billion in 2015, with vendor revenue for the fourth quarter growing 15.7% to $8.2 billion.

This is according to IDC's Worldwide Quarterly Cloud IT Infrastructure Tracker, which notes that compared to overall IT infrastructure spending, the share of cloud IT infrastructure sales climbed to 32.2% in 4Q15, up from 28.6% a year ago.

Revenue from infrastructure sales to private cloud grew by 17.5% to $3.3 billion, and to public cloud by 14.6% to $4.9 billion. In comparison, says IDC, revenue in the traditional (non-cloud) IT infrastructure segment decreased 2.7% year-over-year in the fourth quarter, with declines in all three technology segments (server, storage and Ethernet switch).

All three technology markets showed strong year-over-year growth in both private and public cloud segments, except for storage in the public cloud, which declined 4% in 4Q15.

IDC points out private cloud growth was led by Ethernet switch with 19.6% growth. In public cloud, it adds, Ethernet switch led the way with 56.9% year-on-year growth, while public cloud revenue from server grew 28.9% year-on-year in 4Q15. For the full year, server revenue in private cloud grew by 23% year-on-year, while Ethernet switch revenue in public cloud grew by 36.6% during the same period.

"The cloud IT infrastructure market continues to see strong double-digit growth with faster gains coming from public cloud infrastructure demand," says Kuba Stolarski, research director for computing platforms at IDC.

"End customers are modernising their infrastructures along specific workload, performance and TCO [total cost of ownership] requirements, with a general tendency to move into third platform, next-gen technologies."

Stolarski points out that options on and off premises continue to expand, along with open platforms that enhance hybrid capabilities for a variety of use cases.

"Public cloud as-a-service offerings also continue to mature and grow in number, allowing customers to increasingly use sophisticated, mixed strategies for their deployment profiles. While the ice was broken a long time ago for public cloud services, the continued evolution of the enterprise IT customer means public cloud acceptance and adoption will continue on a steady pace into the next decade," he says.

In Africa cloud solution experts anticipate an increase in the need for cloud solutions as the Internet of Things and big data continue to make an impact.