Software networking startup Pluribus said today it raised $50 million Series D funding, and now claims to be the best-funded private SDN company around, with $95 million in total.

Temasek Holdings Pte. Ltd. , a $177 billion Singapore investment company, led the funding round. Also participating were all previous investors, including New Enterprise Associates (NEA) , Menlo Ventures , Mohr Davidow Ventures and AME Cloud Ventures, as well as new investors Ericsson AB (Nasdaq: ERIC) and NewTech.

Pluribus Networks says it will use the money to expand sales, marketing, business development and engineering.

Pluribus, like other SDN vendors, is trying to make its customer networks more flexible. "Our customers are saying, 'Make my network infrastructure more agile and adaptable so that new applications, new services, and new problems like security can be solved,'" says Pluribus CEO Kumar Srikantan. "I cannot solve it by adding more and more gear and software point products."

Unlike most other SDN and NFV vendors, Pluribus uses a fabric approach, combining hardware, software and storage into a platform for running network applications such as security and analytics. Pluribus offers software for licensing to hardware vendors to run on their own platforms, which accounts for 50% of Pluribus's channel sales. The other half is Pluribus's appliance controller software.

Like Pluribus, Big Switch Networks also takes a fabric approach to SDN.

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Pluribus has more than 40 customers worldwide, with sales in excess of $2 million per quarter, which is a milestone for startups, Srikantan says. "We have achieved that Big Two milestone, and are on the path to a double-digit run rate and beyond."

Customers include Louisiana State University; Lucera -- "they're trying to become the Amazon of low-latency trading infrastructure for major Wall Street Banks," Srikantan explains; and IO Technologies, a data center cloud infrastructure provider.

New investor Tamasek is "the Berkshire Hathaway of networking," says Srikantan. Tamasek invested $7 billion in Alibaba.com Hong Kong Ltd. pre-IPO. Bringing Tamasek in as an investor takes Pluribus beyond the traditional tech VCs on Sand Hill Road, and demonstrates mainstream appeal, Srikantan says.

— Mitch Wagner, , West Coast Bureau Chief, Light Reading. Got a tip about SDN or NFV? Send it to [email protected].