SatCat5, the open-source FPGA Ethernet switch
We've just launched v2.5 of SatCat5, the open-source FPGA Ethernet switch [1]. SatCat5 contains various FPGA building blocks that let you build a custom mixed-media Ethernet switch. It was originally intended for cubesats [2] but has many other potential applications. The headline feature for this release is support for the IEEE-1588 Precision Time Protocol (PTP). SatCat5 has demonstrated end-to-end synchronization to within 50 ps-rms, which is approaching the world-leading performance of CERN's White Rabbit Project [3]. Except we're doing time-transfer over regular, non-synchronous…
SatCat5, the open-source FPGA Ethernet switch launched on March 16, 2024 with 190 votes, #257 of 4,270 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 2 years on.
In plain words
SatCat5 is an open-source FPGA Ethernet switch composed of configurable building blocks for creating custom mixed-media switches. Originally designed for cubesats, it serves applications requiring custom network solutions. Version 2.5 adds IEEE-1588 Precision Time Protocol support, achieving end-to-end synchronization within 50 picoseconds using standard Ethernet through a novel digital timestamping technology. It is licensed under CERN-OHL-W v2.0 and targets developers and engineers building specialized networking hardware.
written from the facts on this page · September 2026
From the sources
SatCat5 is a mixed-media Ethernet switch that lets a variety of devices communicate on the same network. - satcat5/doc/FAQ.md at main · the-aerospace-corporation/satcat5
In the maker’s words, at launch
We've just launched v2.5 of SatCat5, the open-source FPGA Ethernet switch [1]. SatCat5 contains various FPGA building blocks that let you build a custom mixed-media Ethernet switch. It was originally intended for cubesats [2] but has many other potential applications. The headline feature for this release is support…
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