XEP-0220: Server Dialback . This specification defines the Server Dialback protocol, which is used between XMPP servers to provide identity verification. Server Dialback uses the Domain Name System (DNS) as the basis for verifying identity; the basic approach is that when a receiving server accepts
XEP-0199: XMPP Ping . This specification defines an XMPP protocol extension for sending application-level pings over XML streams. Such pings can be sent from a client to a server, from one server to another, or end-to-end. . NOTICE: The protocol defined herein is a Final Standard of the XMPP Standar