Telegram Secret Chats phone number encryption.
Telegram E2EE key exchange phone number.
MTProto end-to-end encryption phone number connection.
Telegram privacy Secret Chats key derivation. Telegram's approach to encryption, particularly end-to-end encryption (E2EE), is a nuanced topic. It's crucial to distinguish between Cloud telegram number database Chats (default chats, group chats, channels) and Secret Chats (optional, one-on-one, E2EE chats). The phone number's role differs significantly between these two types.
1. Cloud Chats (Default Chats): Phone Number as Account Identifier
Encryption Type: Cloud Chats use client-server/server-client encryption (also known as "encryption in transit" and "encryption at rest"). This means:
Messages are encrypted from your device to Telegram's servers.
Messages are encrypted from Telegram's servers to the recipient's device.
Role of Phone Number: In this scenario, the phone number (and its associated User ID) serves as the primary account identifier for:
Authentication: Logging into your account and verifying your identity.
Synchronization: Allowing your messages to sync across all your devices. Telegram needs to know which messages belong to which account to deliver them to all logged-in devices.
Contact Discovery: Your phone number is used to find your contacts on Telegram if you enable contact syncing.
Key Storage: For Cloud Chats, Telegram does hold the encryption keys on its servers (though it claims these keys are stored in separate data centers from the encrypted data itself). This design choice enables cloud synchronization but means Telegram theoretically could access the content if compelled or if its servers were compromised. The phone number is the anchor that ties your data to your account on these servers.
2. Secret Chats (End-to-End Encrypted): Phone Number as a Trust Anchor (Indirect Role).