Secret Chats
Official telegram.org Source
All Telegram messages are always securely encrypted. Messages in Secret Chats useclient-clientencryption, while Cloud Chats useclient-server/server-clientencryption and are stored encrypted in the Telegram Cloud (morehere). This enables your cloud messages to be bothsecureand immediately accessible from any of your devices – even if you lose your device altogether.
The problem of restoring access to your chat history on a newly connected device (e.g. when you lose your phone) does not have an elegant solution in the end-to-end encryption paradigm. At the same time, reliable backups are an essential feature for any mass-market messenger. To solve this problem, some applications (like Whatsapp and Viber) allowdecryptable backupsthat put their users' privacy at risk – even if they do not enable backups themselves. Other apps ignore the need for backups altogether and leave their users vulnerable to data loss.
We opted for a third approach by offering two distinct types of chats. Telegram disables default system backups and provides all users with an integrated security-focused backup solution in the form of Cloud Chats. Meanwhile, the separate entity of Secret Chats gives you full control over the data you do not want to be stored.
This allows Telegram to be widely adopted in broad circles, not just by activists and dissidents, so that the simple fact of using Telegram does not mark users as targets for heightened surveillance in certain countries. We are convinced that the separation of conversations into Cloud and Secret chats represents the most secure solution currently possible for a massively popular messaging application.
> See also:Why Telegram isn't End-to-End Encrypted “by Default”
See also:Why Telegram isn't End-to-End Encrypted “by Default”
Official Telegram Reference: https://telegram.org/faq
Part of the TGWAY.com Official Telegram Knowledge Base (98 Verified Q&As).