LOS ANGELES — SpaceX has won a $2.29 billion firm-fixed-price contract from the U.S. Space Force to build the Space Data Network (SDN) Backbone, with a requirement to deliver a fully operational prototype by the end of 2027. The network will be based on technology originally developed for SpaceX’s Starlink global Internet constellation.

The SDN Backbone will operate in low-Earth orbit and is expected to use the Starshield platform, which SpaceX employs for military satellite applications. "This award will enhance the network with an expanded optically interconnected mesh of satellites delivering worldwide tactical communications and broadband communication services," according to a Space Systems Command statement.

"The network acts as a core communications layer for the USSF war-fighting systems, ensuring our sensors and shooters are connected continuously, globally and securely," said Ryan Frazier, acting Space Force portfolio acquisition executive for Space-Based Sensing and Targeting. He added, "This network leverages the best of commercial innovation and will be a huge benefit and enabler for U.S. military forces."

The Space Data Network evolved from a program previously known as MILNET or pLEO SATCOM. That program replaced planned funding for the next tranche of data transport satellites from the Space Development Agency, which was established in 2019. The agency began launching missile-tracking and data-relay satellite prototypes in 2023. Its original architecture faced delays due to supply chain bottlenecks, integration challenges among multiple contractors, and technical issues identified by the Government Accountability Office.

Jeffrey Fry, SDN Backbone system program manager, said the new acquisition strategy emphasizes both speed and scale. "We aren’t trading speed for scale; we are demanding both," Fry said. He added, "Our acquisition strategy is designed to foster competition and broaden our industrial base." The Space Data Network plans to work with multiple vendors and intends to expand its participant list over the summer, potentially including companies like Amazon that operate their own broadband constellations.

SpaceX currently operates more than 10,000 Starlink satellites for civilian use and hundreds of Starshield satellites for military purposes. When the program was still called MILNET, a Space Force commander indicated it would eventually comprise about 480 satellites operated by SpaceX under military oversight.