How to donload videous for free without be a prime member?
Answers
Telegram's client-side code is open-source software but the source code for recent versions is not always immediately published, whereas its server-side code is closed-source and proprietary. The service also provides APIs to independent developers. In March 2018, Telegram stated that it had 200 million monthly active users. According to its CEO, as of April 2017, Telegram's annual growth rate was greater than 50%.
Messages and media in Telegram are encrypted when stored on its servers, and the client-server communication is also encrypted. The service provides end-to-end encryption for voice calls, and optional end-to-end encrypted "secret" chats between two online users, yet not for groups or channels.
Telegram's security model has received notable criticism by cryptography experts. They criticized the general security model of permanently storing all contacts, messages and media together with their decryption keys on its servers by default and by not enabling end-to-end encryption for messages by default. Pavel Durov has argued that this is because it helps to avoid third-party unsecure backups, and to allow users to access messages and files from any device. Cryptography experts have furthermore criticized Telegram's use of a custom-designed encryption protocol that has not been proven reliable and secure.