I have created several private proxies for my own personal and family use with dd prefix (random padding) but recently all have been blocked in matter of days.
It seems Iran's filtering system can detect telegram proxies even with random padding now.
Who knew that it was not wise to use a custom protocol when you want to bypass Internet filtering ?!
I dont know why Telegram admins are so arrogant. I warned them from the beginning that this encryption method will not work and they have to use SSL/TLS for the traffic to be undetectable.
It is filter bypassing 101:
DO NOT MAKE YOUR TRAFFIC ANY DIFFERENT FROM LEGITIMATE TRAFFIC. IT SHOULD MIX IN. DO NOT USE ANY CUSTOM PROTOCOLS. DO NOT EVEN CHANGE 1 BIT FROM STANDARD PROTOCOLS.

I hope they listen now or Telegram will be dead in Iran. all of my friends are switching to whatsapp already.