Talari Networks has raised $6.2 million to fund further development of it enterprise wide area networking (WAN) gear. The San Jose, Calif.-based company will use the money to expand its research and development operations in Raleigh, N.C.

Menlo Ventures led the round and angel investors participated. The company tries to bring low-cost consumer internet technology to businesses, helping to lower bandwidth costs by 40 to 90 percent.

It has installed equipment for customers such as Finisar, which said it saves several thousand dollars a month in bandwidth costs as a result. Talari uses what it calls “adaptive private networking” for standard secure login technology, virtual private networks and high-speed data delivery. This is helpful for for applications like voice-over-internet-protocol and web video conferences.

The company has 12 employees, and it expects to double that in the coming months. The founders have been working on the technology since 2004. They formally incorporated in 2006. The company was one of the DEMOfall 07 “demogods,” or best of show. Competitors include Juniper Networks’ Perbit division, Riverbed, Cisco, Blue Coat and Silver Peak. Those companies concentrate on optimizing a network so it runs more efficiently.

But Andy Gottlieb, chief executive of Talari, said that about two-thirds of its customers already have gear from those companies and use Talari to get more bandwidth for high-quality applications such as video conferencing and also use Talari to make the whole network more reliable.