sip
simple
xmpp
imps
Answer is Right!
Answer is Wrong!
The correct answer is D. IMPS.
SIP (Session Initiation Protocol) is an application layer protocol for initiating, maintaining, and terminating multimedia sessions over IP networks. It is an IETF standard (RFC 3261).
SIMPLE (Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions) is an IETF standard (RFC 3428) for instant messaging and presence.
XMPP (Extensible Messaging and Presence Protocol) is an IETF standard (RFC 3920) for instant messaging, presence, and group chat.
IMPS (Internet Message Protocol, Simple) is a proprietary protocol used by AOL Instant Messenger. It is not an IETF standard.