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How Is Russia Blocking Calls on WhatsApp/Telegram/Face Time/Snapchat/?

6 points by urcite_ty_kokos ago | 6 comments

urcite_ty_kokos |next [-]

Hi, I was wondering how is it technically possible for Russia firewalls to block calls over these platforms, while keeping chat messages working? Thanks

My guess is that it is because of a different layer 7 protocol than HTTP is used for calls, and the code of the protocol leaks in the TLS/SSL header. Is this guess correct?

doc_doom |next |previous [-]

Ngl same question for United Arab Emirates

belter |previous [-]

Its DPI mostly from this company: https://theins.ru/en/politics/265749

wkat4242 |root |parent |next [-]

It won't be the only solution that can do this by the way. Many airplane WiFi services block WhatsApp and telegram calls.

I think they just look at the traffic shape. Real-time traffic requires a lot of constant similar sized traffic per second, rather than texting or images which is much more bursty.

urcite_ty_kokos |root |parent |previous [-]

Time to learn more on DPI, thanks.

belter |root |parent [-]

If you want to explore and make some tests of your own, nDPI is the most popular open-source DPI engine.

https://github.com/ntop/nDPI

https://youtu.be/NndEp7__Y1A