Total cloud IT infrastructure spending (server, disk storage and Ethernet switch) will grow by 21% year-over-year to $32-billion in 2015, accounting for approximately 33% of all IT infrastructure spending – which will be up from about 28% in 2014.

According to the International Data Corporation (IDC) Quarterly Cloud IT Infrastructure Tracker, private cloud IT infrastructure spending will grow by 16% year-over-year to $12-billion, while public cloud IT infrastructure spending will grow by 25% in 2015 to $21-billion.

For the full year 2014, cloud IT infrastructure spending totalled $26,4-billion, up 18,7% year-over-year from $22,3-billion; private cloud spending was just under $10-billion, up 20,7% year-over-year, while public cloud spending was $16,5-billion, up 17,5% year-over-year.

For this second quarterly release of IDC’s Cloud IT market forecast, IDC has expanded its worldwide coverage to include detail for eight regions: Asia/Pacific (excluding Japan), Canada, Central & Eastern Europe, Japan, Latin America, Middle East & Africa, USA, and Western Europe. In 2015, Western Europe is expected to have the highest growth in cloud IT infrastructure spending at 32%, followed by Latin America (23%), Japan (22%), and the US (21%).

For the five-year forecast period, IDC expects that cloud IT infrastructure spending will grow at a compound annual growth rate (CAGR) of 14%; both public cloud and private cloud are expected to grow at the same CAGR. By 2019, IDC expects cloud IT infrastructure spending to be $52-billion, or 45% of total IT infrastructure spend; public cloud will represent about $32-billion of that amount, and private cloud will account for the remaining $20-billion.

“The pace of adoption of cloud-based platforms will not abate for quite some time, resulting in cloud IT infrastructure expansion continuing to outpace the growth of the overall IT infrastructure market for the foreseeable future,” says Kuba Stolarski, research manager, Server, Virtualisation and Workload Research at IDC.

“As the market evolves into deploying 3rd Platform solutions and developing next-gen software, organisations of all types and sizes will discover that traditional approaches to IT management will increasingly fall short of the simplicity, flexibility, and extensibility requirements that form the core of cloud solutions.”

IDC’s Worldwide Quarterly Cloud IT Infrastructure Tracker is designed to provide clients with a better understanding of what portion of the server, disk storage systems, and networking hardware markets are being deployed in cloud environments. This tracker will break out vendors’ revenue by the hardware technology market into public and private cloud environments for historical data and also provide a five-year forecast by the technology market.