Instant Messaging Protocols

Here's a comparison of notable instant messaging protocols, categorized by their encryption support:

Protocols Without Built-in End-to-End Encryption:

Protocol Name	Description
IRC (Internet Relay Chat)	One of the oldest instant messaging protocols, facilitating real-time text communication. It lacks native end-to-end encryption but supports TLS for server-client encryption.
XMPP (Extensible Messaging and Presence Protocol)	An open-standard communication protocol for message-oriented middleware. While it supports server-to-server and client-to-server encryption (e.g., via TLS), end-to-end encryption requires additional extensions like OMEMO or OpenPGP.

Protocols With Built-in End-to-End Encryption:

Protocol Name	Description
Signal Protocol	Designed for asynchronous messaging with strong end-to-end encryption, used by the Signal app and other platforms.
Matrix	An open communication protocol that supports real-time communication with end-to-end encryption as a default feature for private conversations.
Briar	A peer-to-peer messaging protocol focusing on security and privacy, offering built-in end-to-end encryption without relying on central servers.

Note: Some protocols, such as XMPP, can implement end-to-end encryption through extensions or additional features, but they do not include it by default.