Never expose your raw RTSP camera ports (usually 554) directly to the public internet. Keep your camera inside your local network, and let your local bridge server handle the outbound communication to Telegram's secure servers.
For those who prefer building their own hardware, modules offer an affordable path to custom Telegram-integrated cameras. Projects like the Telegram Security Camera utilize the built-in motion sensor of the ESP32 T-Camera to detect movement and promptly send photo notifications to your Telegram bot.