Look out, Cisco. Facebook is now running on computer networking gear designed by the company's own engineers.

According to Najam Ahmad, who oversees network engineering at Facebook, the company is using its own designs inside at least some of the data centers that underpin its online empire. Facebook has deployed one design, Ahmad says, in "significant quantities."

Last summer, Facebook provided an early look at this design—a networking switch codenamed "Wedge"—and today, it unveiled another, dubbed "Six-Pack." In both cases, the company has built something simpler than the hardware offered by networking vendors like Cisco and Juniper, so that it can more efficiently build, expand, and operate the vast computer networks needed to run its web services, which are now used by more than 1.3 billion people across the globe.

The shift to this custom gear is part of a much larger movement not only at Facebook but across the net. Online giants such as Google, Amazon, Microsoft, and Facebook now design all sorts of hardware for use inside their data centers, working to both reduce costs and improve efficiency in these massive computing facilities. This includes everything from computer servers to data storage gear to networking switches, the devices that shuttle information from machine to machine.

And as these giants move to this new breed of gear—which they typically manufacture through companies in Asia—others are moving in similar directions. Through an organization called the Open Compute Project, or OCP, Facebook shares its designs with the world at large and encourages others to share as well. The result is a new market for cheaper and simpler hardware, much of it manufactured in Asia.

Facebook has not yet "open sourced" its networking designs, but Ahmad says the company will eventually do so. JR Rivers, who helped design networking gear at Google and now helps other businesses adopt similar gear through his company Cumulus Networks, believes that the Facebook designs can help expand this burgeoning market, in part because they're coming from a big name.

"We think that it will be very interesting to other companies," he says. "There may be form-factor modifications along the way, but the architecture is pretty obvious and having them drive helps gets the manufacturers to line up, thus opening up the whole ecosystem."

As this "ecosystem" opens up, it could undermine the Ciscos and the Junipers. But these companies are well aware of this shift and are working to accommodate it, at least in some ways. "Cisco is also a member of the OCP, working closely with Facebook and other members to further open innovations for the industry," Cisco said in a statement sent to WIRED.

Traditionally, Cisco and Juniper sold rather expensive gear that ran proprietary software, and programming this equipment—i.e. building and managing networks—was a relatively difficult process. Facebook and others are now building gear that runs the open source Linux operating system—and that means it can potentially run any software they like. Plus, they've stripping the gear down to its essentials and, in some ways, making it easier to physically construct a vast computer network.

Facebook's "Six-Pack" switch is essentially six smaller switches snapped together. Basically, the company can build bigger switches from smaller ones, and since they all run Linux, its engineers can manage these switches with the same tools used to manage servers across the network.

The end result, Ahmad says, is that Facebook can now build and expand its networks with greater ease—and others are following suit. Ahmad says that Facebook is already working with outside companies interested in using its designs. And Rivers tells us his company, Cumulus, now serves over 200 businesses, both large and small.

Update: This story has been updated with comment from Cisco.