16:00:20 #startmeeting tor anti-censorship meeting 16:00:20 Meeting started Thu Apr 30 16:00:20 2026 UTC. The chair is Shelikhoo[mds]. Information about MeetBot at https://wiki.debian.org/MeetBot. 16:00:20 Useful Commands: #action #agreed #help #info #idea #link #topic. 16:00:20 here is our meeting pad: https://pad.riseup.net/p/r.9574e996bb9c0266213d38b91b56c469 16:00:20 editable link available on request 16:00:30 hi! 16:00:32 hello 16:00:44 hi! 16:00:48 hi~hi~ 16:00:56 hello! o/ 16:01:21 hello 16:02:07 we can start with the first topic now. I will not send the email digest until much later today to allow everyone to update their status. 16:02:09 Network Health is working on an anomaly detection system (P183) 16:02:09 https://censorbib.nymity.ch/pdf/Wright2018a.pdf 16:02:09 https://gitlab.torproject.org/tpo/network-health/tor_anomalies 16:02:09 will discuss next week (Apr 30) 16:02:19 okay 16:02:39 yes, this topic is from geko 16:02:50 i've prepared a pad for that to give you a bit more background info: https://pad.riseup.net/p/project183_anomalies 16:03:27 so, we have this anomalies detection project in network health land which is pretty broad 16:04:05 a core part of it is trying to find algorithms allowing us to detect anomalies in the network quickly 16:04:10 and getting us notified about them 16:04:27 this covers anomalies in bridge users and other parts as well 16:04:47 i've added what we did so far and what is still in the pipeline 16:04:57 and some questions below 16:05:24 most importantly to us, i think, is if the a-c team has something it would like to see happen in this area 16:05:35 we could still try to find time for that, e.g. 16:05:57 I think this is going to be a very useful project 16:06:11 I think the visualizations will be very useful 16:06:20 yeah 16:06:21 and maybe to be able to have in the same page multiple visualizations 16:06:37 we hope we have something better than the current "censorship event page" :) 16:06:54 I find dcf's website very useful: https://people.torproject.org/~dcf/metrics-country.html 16:07:00 not just alghorithm-wise but plain visualization-wise as well 16:07:09 I guess this is more a requests for the webportal 2.0 :P 16:07:40 good requests, though, as that will happen in objective 5 16:08:02 i see you've linked wright's 2018 work and danezis's 2011 work on censorship anomaly detection 16:08:07 are you comparing those two? 16:08:13 yeah, that website done by dcf is a good one 16:08:22 wright did that in their paper 16:08:37 oh i see 16:08:42 we don't do anything beyond that but follow their argument that the detection rate of anomalies is better 16:08:43 I was thinking about regional disconnection, where the internet restriction was applied on a city level rather than state or national level 16:08:44 ah we use danezis' now 16:08:56 yeah that makes sense 16:08:58 and hence we think about using wright's instead 16:09:05 on the website 2.0 16:09:37 while national level censorship get media coverage and a lot of attention that could be documented with traditional methods 16:09:46 Shelikhoo[mds]: yeah, i don't think that we are at a point yet, where we a) have that data available 16:09:55 and b) can do something useful with that 16:09:59 Shelikhoo: the problem of regional based is that relays/bridges provide country metrics, but not regional 16:10:05 yes, thanks GeKo (IRC) ! 16:10:16 but it would def be nice to dive into that at some point 16:10:29 and what meskio[mds] said 16:10:38 I agree, it looks like regional based censorship is becoming more and more a thing 16:10:48 i'm not aware of any more recent work in this area that's specific to tor metrics 16:11:04 there was this somewhat adjacent paper a couple years ago at FOCI: https://www.petsymposium.org/foci/2024/foci-2024-0007.pdf 16:11:58 thanks 16:12:01 something useful might be able to get a list of places where there are anomalies and some graphs of them, I guess this is part of O5 16:12:02 but it uses OONI/Censored Planet/ICLab data 16:12:15 meskio: yes, I think regional level internet shutdown is what are currently insufficiently documented 16:12:18 meskio[mds]: yeah, that will be visualized there 16:12:19 I'm not sure if alerts will not be too noisy and we should just start with some easy to go page 16:12:34 the tor_anomalies tool can already generate country-based graphs, which is pretty nice 16:13:10 yeah, the alert part needs def some tuning 16:13:30 this is maybe a dreaming big feature, but one of the first places i go when seeing weird metrics is OONI, maybe some links or autogenerated OONI plots would be a cool thing to display on the website as well 16:14:01 so like if there is a censorship event for snowflake in RU, an OONI plot of the STUN reachability checks or domain front URL reachability checks 16:14:12 meskio[mds]: we'll loop the a-c team in once we are doing the design for censorship stuff on the website 2.0 16:14:20 cohosh: yeah, that's the big plan 16:14:21 sorry if i'm straying from the objectives too much here 16:14:26 no, no 16:14:32 it's spot-on 16:14:47 however, we'll likely only be able to lay the groundwork for that in this project 16:14:59 we'll have until the end of the year for all the remaining work 16:15:28 yes, but using that groundwork we will also find out what tools we wish on top of it 16:15:32 nice! 16:15:37 indeed 16:15:48 BTW, this is more or less connected to P170 16:16:00 correct 16:16:02 we're we are working on detecting blocked bridges and reporting them to metrics (and to rdsys) 16:16:24 the anomalies visualization and the P170 ones will be useful side by side 16:16:32 alright, i won't take more of your meeting time. happy to discuss things more at any time 16:16:44 and we can use the pad for some async thoughts if needed 16:17:10 thanks for having me here today :) 16:17:12 thank you for bringing the topic, is a nice project 16:17:35 yes, thanks GeKo! 16:17:39 yeah thank you! 16:17:40 sure, anytime! 16:18:00 we have an interesting link this week: 16:18:02 https://github.com/masterking32/MasterHttpRelayVPN 16:18:02 tunnel through https://script.google.com/, currently one of the things used in Iran 16:18:47 I've heard is ratelimited by google so only useful for "smallish" bridges 16:19:04 but very interesting how people is finding new ways to move data around 16:20:16 yeah... I think it would work for Tor after bootstrap. 16:20:38 but for downloading a lot of files, method like this won't work very well 16:20:57 yes, more useful as a signaling channel 16:21:13 I think I did already added it to our wiki list of options 16:21:23 anything more we wants to discuss today? I didn't see any additional discussion topics 16:21:32 not from me 16:22:14 I have a quick question about https://snowflake-broker.torproject.net/prometheus What's the timeframe of the stats? 16:22:14 And a thanks for cohosh for adding "bloco" there. 16:22:55 Is "HELP snowflake_rounded_proxy_answer_total The number of snowflake proxy answers, rounded up to a multiple of 8" since forever? April 28th for "bloco"s case? 16:22:59 SergioSantos: oh good question 16:23:43 It is usually since last restart of the broker 16:24:12 yeah for counters they increase constantly until restart 16:24:13 although if you asked me that is a bad api design by prometheus 16:24:17 maybe this is more useful for you: https://snowflake-broker.torproject.net/metrics 16:24:23 is those are daily counters 16:24:24 Just noticed a restart šŸ˜… 16:24:34 yeah haha i just restarted again now 16:24:40 to apply a bug fix 16:24:53 see that each day has a 'snowflake-stats-end'... 16:26:08 Oh nice, 58 bloco IPs yesterday then 16:26:22 nice 16:26:29 nice! 16:27:03 We had around 70 downloads from github + google play for now. F-droid almost there. So that makes sense. 16:27:05 wow that's pretty good 16:27:12 No daily stats for answers? 16:27:20 that's cool! 16:27:49 no stats for answers, those were a more recent metric to try and track down the cuase of rendezvous failures 16:28:02 https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowflake/-/work_items/40447 16:28:37 we just implemented them for prometheus as a debugging attempt 16:29:08 it's harder to define what it means because an answer is only processed if the client connection hasnt timed out already 16:29:15 Thanks for the answers. I'll keep an eye on the daily IP stats then. 16:29:35 nice! anything more we wants to discuss in this meeting? 16:29:48 May I ask you one thing? 16:29:56 please go ahead! 16:30:23 At last week’s meeting, I heard that cohosh would be taking on the UAT code review. Based on the information in MeetingPad, is my understanding correct that this will begin immediately next week? 16:30:36 i will start reviewing the code next week 16:30:53 it might take a while and we have some other time-sensitive tasks to do this month 16:31:03 but i'll try to give you frequent updates on the issues you opened 16:31:20 so that you are up to date on how it's progressing 16:31:45 I see. Thank you very much. 16:32:31 thanks for keeping up with it :) 16:32:43 nice! thanks~ 16:33:02 anything more we would like to discuss in today's meeting? 16:33:06 I’d like to share one thing: since you’ve agreed to conduct a code review, I submitted a pull request yesterday to implement WebPKI, keeping practical implementation in mind. 16:33:13 oh sorry 16:33:26 don't worry it is fine 16:33:39 oh okay, a pull request to your own repository or to one of ours? 16:33:44 I'm not very good at English, so it's taking me a while to type this. I apologize. 16:33:54 no problem at all, we have plenty of time 16:33:57 and nice work on supporting webPKI 16:34:48 I believe there is a branch called ā€œfeat/wbpkiā€ in the UAT branch, so I would appreciate it if you could check it. 16:36:48 https://gitlab.torproject.org/41_un/uat/-/tree/feat/webpki?ref_type=heads 16:36:51 I see it is here 16:37:03 https://gitlab.torproject.org/41_un/uat/-/merge_requests/4 16:37:21 okay great 16:37:27 and a merge request is created for it already, and the discussion can be continued asyncly there 16:37:54 I have also conducted tests using self-signed certificates as before and confirmed that they work; however, since I currently do not have an environment where I can actually run WebPKI (VPS, domain, valid certificate), it is not yet clear whether WebPKI will function fully in practice. 16:37:57 thank you 16:38:46 I have to head out for an appointment but thanks for running the meeting @Shelikhoo ! and thanks everyone :) 16:39:01 thanks onyinyang ! 16:39:35 What should I do in this case? I could rent a VPS or something similar to test it myself, but that might take a little time. (I’m currently a student and don’t have much money...) 16:40:26 I think the reviewer can check if it actually works during the review process 16:40:28 M4i_un[mds]: i can probably test it out when i do the review 16:40:34 i have a few domains and boxes i can use 16:40:46 you can also create your own ca for development purpose 16:41:14 I see. That puts my mind at ease. 16:41:14 https://github.com/OpenVPN/easy-rsa 16:43:01 In that case, would it be okay if I asked you to verify that the WebPKI is working properly? I’ll also do my best to test it here. 16:43:27 yes i'll update you on the merge request 16:43:55 Thank you very much for your cooperation. 16:44:46 nice! 16:44:46 That’s all I wanted to ask and share! Thank you for your time! 16:45:08 anything more we wants to discuss in this meeting? 16:46:27 thanks!!!! 16:46:28 https://github.com/OpenVPN/easy-rsa 16:46:34 #endmeeting