Two-year-old startup Avi Networks on Wednesday launched general availability of its cloud-based application delivery controller (ADC) and confirmed that it has raised a total of $33 million over two funding rounds.

Sunnyvale, Calif.-based Avi has attracted a slate of prominent backers. Menlo Ventures led the Series B round, which closed in August of this year and brought Avi's total funding to $33 million. Greylock Partners and Lightspeed Venture Partners joined the latest funding round after co-leading a previously undisclosed $12.2 million Series A in 2012.

Avi hopes to capitalize on the enterprise migration to the cloud with its software-based ADC. Called Cloud Application Delivery Platform (CADP), the product's virtual engines perform Layer 4-7 functions such as load balancing and SSL termination.

The ADC market is expected to top $2.2 billion worldwide by 2018, according to IDC research director Brad Casemore. For a piece of that market, Avi will be up against established players such as F5 Networks, Citrix Systems, A10 Networks, and Radware.

Avi Networks CEO Umesh Mahajan, a former vice president of data center switching at Cisco, positions his company as bringing the ADC into the cloud era, offering features such as the ability to automatically add more virtual instances in order to scale alongside an application. F5, the biggest vendor in traditional ADCs, already offers a virtual ADC, but Mahajan dismisses it: "F5 have taken the software that they have in their appliances and put it in a virtual machine," he says.

Others will likely soon follow, including startup Versa Networks, according to industry rumors.

"There are plenty of data centers and applications out there that won’t move to the cloud anytime soon," ESG analyst Jon Oltsik notes in an email. "In the meantime, others will virtualize their ADCs."

Avi's virtual ADC is sold on a subscription model, where Avi charges not for every CADP engine used, but for every instance of the application that the CADP is tied to. In other words, using CADP virtual machines to help an application costs just as much as using three CADPs with that same application.

Avi employs about 50, most of them in Sunnyvale. At press time, the company was planning to announce one customer on Wednesday: Hitachi America Ltd.