1. Introduction

1.1. Overview

   The Extensible Messaging and Presence Protocol (XMPP) is an open
   Extensible Markup Language [XML] protocol for near-real-time
   messaging, presence, and request-response services.  The basic syntax
   and semantics were developed originally within the Jabber open-source
   community, mainly in 1999.  In 2002, the XMPP WG was chartered with
   developing an adaptation of the Jabber protocol that would be
   suitable as an IETF instant messaging (IM) and presence technology.
   As a result of work by the XMPP WG, the current memo defines the core
   features of XMPP 1.0; the extensions required to provide the instant
   messaging and presence functionality defined in RFC 2779 [IMP-REQS]
   are specified in the Extensible Messaging and Presence Protocol
   (XMPP): Instant Messaging and Presence [XMPP-IM].

1.2. Terminology

   The capitalized key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
   "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14, RFC 2119 [TERMS].