Tor is is blocked in Iran.
Iran can block these proxies, too, but this way there isn't any centralized listing of proxies. This proxy setup is simple enough that a single person could run a proxy for a few dozen of their friends, and the Iranian government might just never find out about it.
I fear that some naive Western expat will participate and find themselves in a hostage. Many countries in this don't have any treaties with Western nations, they dont have high regard for human rights either.
https://2019.www.torproject.org/docs/bridges.html.en#Pluggab...
One could use censorship evading VPNs like Tor, Lantern, Shadowsocks, Psiphon in addition to using these proxies. They all have different evasion mechanisms.
The thing that works for user-run proxies is, it is like a hydra, you censor one proxy another crops up.
Regardless, I hope this does actually end up working, and allows Iranians to use Signal without a prolonged cat-and-mouse game.
The TLS proxy signal just advertised uses plaintext TLS SNI header to determine where to route the packets, which makes it really trivial to detect and/or block. The same cannot be said about tor.
Signals TLS proxy is naive compared to obfs4, but at it’s core it’s a similar solution.
So no, it's not 'blocked'. They're just trying. Mostly by blocking bridges they know of.