Network Functions Virtualization (NFV) is gaining traction in mobile networks, and mobile infrastructure startup Affirmed Networks is emerging as one of the leaders.

Acton, Mass.-based Affirmed focuses on virtualized infrastructure for mobile Evolved Packet Core (EPC), the gear needed for mobile data networks at 3G, 4G, and beyond. It has closed a number of deals in the first quarter of 2015 to bring its customer count to 23. At least four of Affirmed's customers are so-called "Tier 1" (large) service providers, including AT&T and S. Korea's LG U+. Other significant customers include Transatel, based in France, and Elephant Talk, an international provider based in New York.

Affirmed made a big splash when it made AT&T's list of Domain 2.0 vendors in 2013. This was the list of technology suppliers that AT&T announced it was working with on its next-generation Software Defined Networking (SDN) platforms.

The customer deals should silence critics who have said global service providers aren't ready for NFV -- it's clear they are deploying it. Service providers say they want to use NFV technology to deploy services more quickly and with more flexibility. NFV is seen as more flexible because it takes functions that were previously deployed on purpose-specific hardware and deploys them with software on commodity server hardware platforms, which is often referred to as Commercial Off the Shelf (COTS) hardware.

Affirmed is using the NFV model to deploy many different EPC functions on COTS hardware, and its customers cite this approach as cheaper and faster.

"Clearly NFV is a trend that has gone mainstream and has garnered global attention as a result of the many benefits of this new type of architecture to MNOs to replace their legacy systems," wrote Martin Zuurbier, Co-President, Mobile Platform Business, with Elephant Talk, in an email.

In addition, it's easier to integrate a software-based technology. Many different mobile functions that were previously offered on different platforms can be combined in a software package. Affirmed offers a range of software-based functions for 3G/4G mobile networks including Serving GRPS Support Node (SGSN), Mobile Management Entity (MME), and mobile gateways. The solutions also include functions for policy control, security, and service creation.

"With a software solution there is 30 to 40% savings," says Angela Singhal Whiteford, Affirmed's VP of Marketing. "It's also a service buy, for service creation. We turn up the service in three months."

Affirmed has customers in four global markets, including Japan, Korea, Western Europe, and North America. Korea's LG U+ is the most recent addition, announced last month. LG U+ is using Affirmed to deploy an EPC network.

Officials from LG U+ say the NFV approach will allow it to speed up delivery of new services, including LTE-U (Unlicensed) introduced last year. The service provider says it completed a trial test with Affirmed last year and will be scaling the new virtualized EPC-based services this year.

“We decided to build vEPC earlier in order to respond flexibly towards growing video traffic demands and customers' various needs in IoT and 5G environment," said a statement from LG U+ in a March 16 press release.

Another customer, Finnish wireless operator Ukkoverkot, was announced in early March. It is using Affirmed in the deployment of its 450 MHz Ukko Mobile 4G LTE data services. It cited the scaleability and flexibility of the Affirmed software approach in a press release.

All of this bodes well, not just for Affirmed, but for those using next-generation NFV technology in service-provider networks. It's clear that NFV has their attention because of the potential for cost savings and faster service delivery.

Affirmed is led by CEO and Chairman Hassan M. Ahmed, who was formerly CEO of Sonus Networks (Nasdaq: SONS). It was founded in 2010 and launched its first product in 2012. The company has received a total of $163 million in three rounds of funding. In June 2013 it announced that it had raised $51 million in funding, led by Bessemer Venture Partners and joined by KCK Group. Other investors in the company include Charles River Ventures, Matrix Partners, Lightspeed Ventures, T-Venture, and Vodafone Ventures.