Space Development Agency (SDA) Director Derek Tournear said on Apr. 14 that he views cyber and supply chain threats to the National Defense Space Architecture’s (NDSA) Transport Layer as more significant ones than ground-based direct ascent anti-satellite (DA-ASAT) and laser weapons.

The NDSA will effectively be an optically-connected Internet in space to provide tactical data–low latency communications and targeting information–to military forces in the field.

SDA believes that the projected hundreds of low-cost Transport Layer satellites–each less than $14 million–will help deter DA-ASAT attacks, while the 1,000 kilometer polar orbit of the satellites will help protect them against ground-based directed energy attacks.

“Cyber and supply chain are two of the threats that I’m concerned about,” Tournear told the Washington Space Business Roundtable (WSBR) on Apr. 14. “Cyber and supply chain problems are common mode failures so it doesn’t matter, if I have one satellite or a thousand satellites, those [problems] may have the ability to take them all out. So those are the threats that I’m most focused on because those are the ones that I think can have the biggest, devastating effect, whereas the other threats, I actually think proliferation [of satellites] gives us significant advantages. In fact, I would go so far as to say that [for] Tranche 1 and beyond, it will cost more to shoot down a satellite than the satellite cost to actually put up there and operate so we’ve completely changed the equation on that.”

Because of the envisioned cyber and supply chain threats to the Transport Layer, SDA is engaging in cybersecurity efforts, and Tournear said on Apr. 14 that he favors limiting the suppliers on certain portions of the layer–such as flight computers–to domestic vendors.

SDA is focused on providing space-based beyond-line-of-sight targeting of mobile missile systems, ships, and advanced missiles, including hypersonic ones, within seconds. The backbone of NDSA, the Transport Layer, is to provide the targeting of ground and maritime targets, while the Tracking Layer–the Next-Generation Overhead Persistent Reconnaissance (Next-Gen OPIR) constellation–is to establish effective targeting of advanced missiles. In addition, SDA is working  to aid future intelligence, surveillance, and reconnaissance (ISR) satellites in the Custody Layer to fuse ISR tracking with the Transport Layer to devise the best targeting solution.

SDA is to field 150 small size, weight and power laser communications satellites in Tranche 1 of the Transport Layer by September, 2024 and is to field additional tranches every two years. Such mesh network satellites are to provide the rapid targeting of ground and maritime targets to military forces over Link 16. The optically-connected satellites will also supply position, navigation and timing (PNT) to U.S. and allied forces in GPS-denied environments.

Last August, SDA awarded $281.5 million in firm, fixed-price contracts to Lockheed Martin [LMT] and York Space Systems to build 10 satellites each for Tranche O of the Transport Layer (Defense Daily, Sep. 1, 2020).

The 20 satellites are to launch by September next year.

The 10 satellites to be launched by each company for the mesh network consist of seven in Class A and three in Class B. A Class A satellite will have at least four optical cross links to other satellites in the same or different orbits, while a Class B satellite will have two optical cross links to furnish constant communications among other satellites in the transport layer and a Link 16 transmitter to communicate with front-line forces.

To connect with the National Defense Space Architecture’s Transport Layer, the U.S. Air Force and U.S. Space Force Advanced Battle Management System is to have a GatewayONE waveform translator, a RadioONE software-defined radio, and an ApertureONE common aperture for communications and radar. The latter three methods are to allow the dissemination of data to military forces in the field without Link 16 or another tie to the SDA Transport Layer.