[tor-relays] bridge distribution mechanism

[Roger Dingledine]

On Sun, Dec 12, 2021 at 10:52:42AM +0100, trinity pointard wrote:
> There are multiple bridges distributions mechanism. One is chosen at random
> when your bridge first come to life, each being perfectly fine :
> - moat: distributed automatically to Tor Browser users
> - https: distributed on bridge-db website after solving a captcha
> https://bridges.torproject.org/
> - email: distributed when sending an email to bridges at torproject.org)
> - reserved: distributed manually, mostly in-person I imagine
> 
> The only distribution mechanism you might want to worry about is "none", it
> either mean your bridge is really young and bridge-db is not distributing
> it yet (it should only be in that state for about a few hours), or you
> decided to distribute this bridge yourself (no bridge-db involved, by
> setting  `BridgeDistribution none` in your torrc), or your bridge is down.

Right, exactly.

Two more documentation resources that could be helpful:

* The relay-search page makes each "Bridge distribution mechanism"
into a link to its entry on
https://bridges.torproject.org/info

* You can read about the original design idea here:
https://svn-archive.torproject.org/svn/projects/design-paper/blocking.html#tth_sEc7.4

And for those who enjoy reading even more, check out these blog posts
which detail the open research areas:
* https://blog.torproject.org/strategies-getting-more-bridge-addresses
* https://blog.torproject.org/research-problems-ten-ways-discover-tor-bridges
* https://blog.torproject.org/research-problem-five-ways-test-bridge-reachability

--Roger