The WAN optimization segment is faring better than other networking segments, with sales up 7 percent to $256 million in Q4 2009.

And that's just the first bit of good news from according to Infonetics' latest quarterly report, titled "Data Center Network Equipment."

Additionally, Data center switches continue to account for the bulk of data center network equipment revenue. Data center Ethernet switches hit $3.2 billion in 2009, capped by a very strong fourth quarter, indicating resurgence in data center build-outs, along with the general recovery in network equipment sales.

"Cisco (News - Alert) continues to dominate the overall data center network equipment market, as few vendors can match the breadth of Cisco's product portfolio," said Matthias Machowinski, Infonetics Research's (News - Alert) directing analyst for enterprise voice and data.

According to the report, purpose-built and blade switches are forecast to take increasing share of the data center switch market, as these switches better address the requirements of the next generation data center, including the move to blade server platforms, SAN convergence and high performance. Infonetics noted that application delivery controller (ADC (News - Alert)) sales increased 14 percent in Q4 09 from the previous year.

Infonetics' quarterly report "Data Center Network Equipment" is a new service that provides worldwide and regional market size, market share, forecasts through 2014, and in-depth analysis for data center Ethernet switches (general purpose, purpose-built, and blade switches), application delivery controllers, and WAN optimization appliances.

Companies tracked in the report include 3Com/H3C, ADTRAN, Alcatel-Lucent, Allot (News - Alert), Arista, Blade, Blue Coat, Brocade, Cisco, Citrix Netscaler, D-Link, Enterasys, Expand, Extreme, F5, Force10, HP, Huawei, Ipanema, Juniper, Linksys, NETGEAR, Nortel, Packeteer, OneAccess, Radware, Riverbed (News - Alert), Silver Peak, SMC and others.