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A new space race is imminent, with several industry players working towards satellite-based Internet connectivity. While satellite networks are not themselves new, these recent proposals are aimed at orders of magnitude higher bandwidth and much lower latency, with constellations planned to comprise thousands of satellites. These are not merely far future plans-the first satellite launches have already commenced, and substantial planned capacity has already been sold. It is thus critical that networking researchers engage actively with this research space, instead of missing what may be one of the most significant modern developments in networking. In our first steps in this direction, we find that this new breed of satellite networks could potentially compete with today's ISPs in many settings, and in fact offer lower latencies than present fiber infrastructure over long distances. We thus elucidate some of the unique challenges these networks present at virtually all layers, from topology design and ISP economics, to routing and congestion control.

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Buoyed by advances in space technology, several firms are planning satellite constellations to offer broadband Internet service. While these developments are happening quickly, there are also many uncertainties about the design of these networks. A key open question is whether or not they will incorporate direct connectivity between satellites, instead of only ground-satellite connections. We compare the network behavior resulting from the two outcomes of that question. Our analysis shows that inter-satellite links substantially reduce the temporal variations in latency, add greater resilience to weather, and could yield more than 3× the throughput achieved without such links. Thus, whether this one design element pans out could have a large bearing on the performance, reliability, and economics of these networks. CCS CONCEPTS • Networks → Physical links; Network performance modeling.

Space industry upstarts are deploying thousands of satellites to offer global Internet service. These plans promise large improvements in coverage and latency, and could fundamentally transform the Internet. But what if this transformation extends beyond network transit into a new type of computing service? What if each satellite, in addition to serving as a network router, also offers cloud-like compute, making the new constellations not just global Internet service providers, but at the same time, a new breed of cloud providers offering "compute where you need it"? We examine, qualitatively and quantitatively, the opportunities and challenges of such in-orbit computing. Several applications could benefit from it, including content distribution and edge computing; multiuser gaming, co-immersion, and collaborative music; and processing space-native data. Adding computing hardware to a satellite does not seem prohibitive in terms of weight, volume, and space hardening, but the required power draw could be substantial. Another challenge stems from the dynamics of low Earth orbit: a specific satellite is only visible to a ground station for minutes at a time, thus requiring care in managing stateful applications. Our exploration of these trade-offs suggests that this "outlandish" proposition should not be casually dismissed, and may merit deeper engagement from the research community. CCS CONCEPTS • Networks → Cloud computing.