How Telegram's MTProto FakeTLS Proxy Evades Censorship and Deep Packet Inspection

MTProto proxies with FakeTLS help users bypass Telegram blocks imposed by ISPs or national firewalls by disguising traffic as standard TLS 1.3 connections to legitimate domains like microsoft.com. Deep Packet Inspection cannot distinguish a real user's connection from a normal HTTPS visit, and active probes by censors are silently redirected to the actual fronting domain. Unlike VPNs, MTProto proxies are Telegram-specific, require minimal setup, and impose negligible battery or speed overhead. A key production pitfall is clock drift: if a proxy host's system clock deviates by more than a few minutes, all client handshakes fail silently while the proxy still appears operational. Running NTP time-sync software like chrony on every proxy host is essential to prevent this failure mode.