I've drafted a year-in-review post for Snowflake users in 2023 that doubles as a request for donations for running the bridge. I'm planning to post it to the Tor forum.
Is there anything to add?
Erik: is the quoted hosting costs of €4,800 correct?
The post discusses both existing bridges. We could also do one specifically for snowflake-01 to post to the Open Collective.
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This is a summary of usage of the [Snowflake](https://snowflake.torproject.org/) pluggable transport in 2023. For the previous year's summary, see the [Snowflake 2022 year in review](https://opencollective.com/censorship-circumvention/projects/snowflake-daily...).
The primary Snowflake bridge, called snowflake-01, is supported by donations. In 2023, the [Snowflake Daily Operations team](https://opencollective.com/censorship-circumvention/projects/snowflake-daily...) spent about [€4,800](https://opencollective.com/censorship-circumvention/projects/snowflake-daily...) to keep the bridge running—with most of that going to pay for bandwidth. In 2024, we would like to buy new hardware for the bridge, which will enable it to support more users at the busiest times of day. You can help by [donating to support the bridge](https://opencollective.com/censorship-circumvention/projects/snowflake-daily...).
[Donate funds for the snowflake-01 bridge](https://opencollective.com/censorship-circumvention/projects/snowflake-daily...)
Let's start by looking at the daily users and bandwidth. Tor user graphs show an estimate of the [average number of simultaneously connected users](https://metrics.torproject.org/reproducible-metrics.html#users). For instance, if the line passes through 50,000, it means there were, on average, 50,000 users using Snowflake at the same time on that day. The bandwidth graph shows the total amount of Tor traffic transferred per day.
While there were fewer users at the end than at the beginning of the year, Snowflake users are using greater total bandwith, now about 35 TB per day.
[snowflake-userstats-bridge-transport-2023.png]
[snowflake-bandwidth-2023.png]
These are some of the events that affected Snowflake usage in 2023:
* Between 2023-01-16 and 2023-01-24, and intermittently thereafter, domain fronting rendezvous was [blocked in parts of Iran](https://bugs.torproject.org/tpo/anti-censorship/team/115). As more Snowflake users are in Iran than in any other country, this resulted in an observable decrease in the number of users. * On 2023-03-13, the Tor anti-censorship team [fixed a security bug](https://forum.torproject.org/t/security-advisory-cross-user-tls-traffic-mixi...) that had also negatively affected performance since September 2022. This greatly improved bandwidth for all users. * The big drop in users on 2023-09-20 was not caused by a censor. Rather, it was an [unexpected change](https://forum.torproject.org/t/problems-with-snowflake-since-2023-09-20-brok...) in the infrastructure used by Snowflake for rendezvous. Mitigating the problem required new software releases.
Before 2023, we had used just one, centralized Snowflake bridge. Last year we started using [a second bridge](https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...) in order to scale to more users. Here are the same user and bandwidth graphs, but with the snowflake-01 and snowflake-02 bridges shown separately:
[snowflake-userstats-bridge-transport-multi-2023.png]
[snowflake-bandwidth-multi-2023.png]
We can also break down users by country. The largest contingent of Snowflake users are in Iran, which has been the case since [the Mahsa Amini protests in 2022](https://ooni.org/post/2022-iran-blocks-social-media-mahsa-amini-protests/). The graph shows also a large number of users apparently from the United States, but we believe that may be partly the result of geolocation errors, and many of them are [actually from Iran](https://bugs.torproject.org/tpo/anti-censorship/pluggable-transports/snowfla...). After Iran, the countries with the most Snowflake users are Russia and China. On 2023-04-10 the team [fixed a bug](https://bugs.torproject.org/tpo/anti-censorship/pluggable-transports/snowfla...) in the browser proxy that caused some users to be wrongly attributed to the unknown `??` country code. The reason for the per-country estimates becoming less precise from October to December was a [user-counting bug](https://bugs.torproject.org/tpo/core/tor/40871) in Tor that existed from version 0.4.8.4 until 0.4.8.10.
[snowflake-top-countries-2023.png]
