Vendors of data center networking equipment have made 17% more revenue in the first quarter of the year than they did during the first three months of 2011, market-research firm Infonetics Research reported.

Sam Barnett, directing analyst for data center and cloud at Infonetics, said, while overall market revenue was down sequentially, the market was “up nicely” from one year ago.

“For the remainder of 2012 and into 2013, we expect growth to be choppy as service providers and data center operators are at different stages in their data center upgrades and some are beginning to wind down their current investment cycle,” Barnett forecasted.

Global revenue generated from sales of data center networking equipment, including Ethernet switches, application delivery controllers (ADC) and WAN (Wide Area Network) optimization appliances, reached US$2.2bn in the first quarter. That was 6% less than the vendors reported in the fourth quarter of 2011.

WAN optimization appliance revenue declined the most from the preceding quarter: by 20%.

Cisco had more than 50% of the market. HP and F5 tied for the next biggest market share (see infographic at the top).

Nearly half of the vendors’ total revenue came from North America, while strongest sequential growth happened in Asia-Pacific markets.

Investments in the European markets are down because of renewed fears of an economic meltdown in the European Union. Overall EMEA data center networking revenue was down 10% sequentially, making the region the world’s worst-performing for the product category.