Ask HN: How does UAE block encrypted calls like Watsapp and Telegram?

This might be a better question on the StackExchange for Information Security [0], they'll give you better and more in-depth explanations than what Hacker News was designed for.

[0]: https://security.stackexchange.com/

Possibly related thread that I commented in last year:

https://news.ycombinator.com/item?id=12039133