The great goal of Elon Musk’s Starlink and other satellite Internet projects is to provide high-speed, low-latency broadband Internet around the world. But there are still some important questions that need to be answered, including how to build a secure and resilient network in space.
To examine such questions, Commonwealth Cyber Initiative (CCI) Virginia Tech researchers have partnered with the University of Surrey in the UK to build the world’s first in-circuit hardware testbed that emulates the changing connectivity of a constellation of mega-satellites at scale. The researchers presented the test bed at an intercontinental workshop on July 12 and 13.
“We wanted to establish a shared community vision and brainstorm about what would be possible and what would be most useful in a space networking infrastructure,” said CCI researcher Jonathan Black, a professor of aerospace engineering.
In addition to bringing together researchers and funding agencies on both sides of the Atlantic, the interdisciplinary workshop engaged members of the aerospace and satellite community, as well as the computer networking and communications communities, including researchers from Wireless @ VT in the Bradley Department of Electrical and Computer Engineering and the Space Science and Engineering Research Center (Space@VT).
Speakers at the workshop included representatives from NASA’s Goddard Space Flight Center and the National Science Foundation, as well as Ella Atkins, president of Fred D. Durham and incoming department chair for the Kevin T. Crofton Department of Aerospace and Ocean Engineering.
“To repair, upgrade and refuel in space, we need to build for efficiency and disruption,” said Atkins, who called the shop from his rural home via Starlink. “By grounding communications and networking in space robotics for the long term, our researchers are building the future of space engineering.”
According to Atkins and Black, the future of space engineering requires effective communication, and the next step is to connect satellite networks.
Breaking down space silos
On land, network Internet service providers are interconnected. A user on the Verizon network can talk to someone on an AT&T network, for example. Communication bounces between networks.
In space, however, communications are isolated. The mega-constellations of satellites that make up different space networks do not communicate with each other, between orbits, between networks, or between individual satellites.
“We want all networks to communicate securely and efficiently,” said Black, who also serves as director of the Aerospace and Ocean Systems Division at the National Security Institute and co-director of the Space Science and Engineering Research Center. “The workshop and test bed directly link to make this happen, interconnecting the various space networks in constellations and pivoting towards 5g/NextG wireless communications capabilities.”
Test interconnectivity, build for resilience
With the support of the Commonwealth Cyber Initiative, the Virginia Tech team and its partners have been investigating new high-bandwidth space networks. The testbed they’ve developed over the past year will simulate internet mega-constellations, including satellites, ground stations, connected devices like phones, and the links between them all.
“We have on the order of thousands of simulated spacecraft as nodes,” said Samantha Parry Kenyon, Space@VT research associate and co-principal investigator of the CCI project. “We can physically communicate with the hardware nodes and incorporate them directly with the virtual satellite nodes in the simulation.”
By running the testbed through different scenarios, the team is looking at what to do when operations are disrupted by something like a space event or security breach and how an adjacent satellite network might compensate for a compromised system.
Resilience is about how a system responds to unexpected changes, Black explained. “The network must be able to continue to operate even when degraded.”
With the help of Virginia Tech Integrated Center for Security Education and Research, the team plans to open up the testbed reference architecture and allow others Commonwealth Cyber Initiative institutions, researchers, educators, and students to examine and optimize pathways toward connectivity between constellations.
With the ability to model constellations at the scale of Starlink, researchers will be able to design resilient, secure and interconnected networks, both hardware and software.