How can QUIC be viable, then? The attentive reader might already have spotted the answer: the problem isn’t QUIC, but its default configuration, which was designed with terrestrial internet in mind. What we need is a custom configuration, this time targeting deep space, with guidelines to tweak things further if a space mission deems it necessary.

See https://datatracker.ietf.org/doc/draft-many-tiptop-quic-profile/01/

To run the experiments in real time instead of time delays in space:

• the clock can advance way faster than normal and elapse whenever the process got blocked due to a timer
• get rid of packet IO and use one process simulating the whole thing.

With full control over the network, it became possible to make the workbench fully deterministic

Debuggability received some love too. As packets travel through the in-process network, each peer records them in a synthetic .pcap file for later inspection.

More details in the post to make it work.