On Tue, Nov 10, 2026 at 02:57:49PM +0100, Clara Engler via tor-dev wrote:

Hi tor-dev@, I have written a torspec proposal to remove extra-infos and include their relevant fields directly inside router descriptors instead.

The motivation for this including the full text of the proposal can be found here: https://gitlab.torproject.org/tpo/core/torspec/-/merge_requests/565

I think this is a good idea, worth investigating more. Three thoughts: (1) Relays generally don't fetch the extra-info descriptors, so actually separating them saves quite a bit of bandwidth/storage on relays. Not a big deal maybe but worth keeping in mind. It could be helpful to get some actual numbers here. (2) We have a few security bugs open currently for mismatches, de-syncs, and other edge cases around extrainfo descriptors. See for example https://gitlab.torproject.org/tpo/core/tor/-/work_items/41433 (sorry it's still confidential). So, we could save current and future security triage and patch headache by moving to the simpler design. (3) In terms of effort, the decision is "do we save more time on Arti implementation plus future C-Tor and Arti maintenance than we spend making the switch in C-Tor?" This choice is made trickier by the bottleneck we have currently in C developers. I expect dgoulet's opinion will weight heavily here. (3b) It also reminds me of how much I miss having an alpha branch in C-Tor these days. This change would be a lot more comfortable doing it in an alpha first rather than pushing it directly into a new stable. --Roger