Network Working Group P. Saint-Andre Internet-Draft JSF Expires: December 8, 2005 June 6, 2005 An Internationalized Resource Identifier (IRI) Scheme for the Extensible Messaging and Presence Protocol (XMPP) draft-saintandre-xmpp-iri-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on December 8, 2005. Copyright Notice Copyright (C) The Internet Society (2005). Abstract This document defines an Internationalized Resource Identifier (IRI) scheme for use in identifying or interacting with entities that can communicate via the Extensible Messaging and Presence Protocol (XMPP). Saint-Andre Expires December 8, 2005 [Page 1] Internet-Draft XMPP-IRI June 2005 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 2. Description of xmpp: IRI Scheme . . . . . . . . . . . . . . . 3 2.1 Rationale . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Form . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3 Authority Component . . . . . . . . . . . . . . . . . . . 5 2.4 Path Component . . . . . . . . . . . . . . . . . . . . . . 6 2.5 Query Component . . . . . . . . . . . . . . . . . . . . . 6 2.6 Fragment Identifier Component . . . . . . . . . . . . . . 7 2.7 Generation of XMPP IRIs . . . . . . . . . . . . . . . . . 8 2.8 Processing of XMPP IRIs . . . . . . . . . . . . . . . . . 9 2.9 Internationalization . . . . . . . . . . . . . . . . . . . 10 3. IANA Registration of xmpp: IRI Scheme . . . . . . . . . . . . 10 3.1 IRI scheme name . . . . . . . . . . . . . . . . . . . . . 10 3.2 IRI scheme syntax . . . . . . . . . . . . . . . . . . . . 11 3.3 Character encoding considerations . . . . . . . . . . . . 11 3.4 Intended usage . . . . . . . . . . . . . . . . . . . . . . 11 3.5 Applications and/or protocols which use this scheme name . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.6 Security considerations . . . . . . . . . . . . . . . . . 12 3.7 Relevant publications . . . . . . . . . . . . . . . . . . 12 3.8 Person and email address to contact for further information . . . . . . . . . . . . . . . . . . . . . . . 12 3.9 Author/change controller . . . . . . . . . . . . . . . . . 12 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 5. Security Considerations . . . . . . . . . . . . . . . . . . . 12 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.1 Normative References . . . . . . . . . . . . . . . . . . . 12 6.2 Informative References . . . . . . . . . . . . . . . . . . 13 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 15 Intellectual Property and Copyright Statements . . . . . . . . 16 Saint-Andre Expires December 8, 2005 [Page 2] Internet-Draft XMPP-IRI June 2005 1. Introduction The Extensible Messaging and Presence Protocol (XMPP) is a streaming XML technology that enables any two entities on a network to exchange well-defined but extensible XML elements (called "XML stanzas") in close to real time. As specified in [XMPP-CORE], entity addresses as used in communications over an XMPP network must not be prepended with a Uniform Resource Identifier (URI) scheme (as specified in [URI]). However, applications external to an XMPP network may need to identify XMPP entities as URIs or, in a more modern fashion, as Internationalized Resource Identifiers (IRIs) as specified in [IRI]. (Examples of such applications include databases that need to store XMPP addresses and non-native user agents such as web browsers and calendaring applications that provide interfaces to XMPP services.) The format for an XMPP address is defined in [XMPP-CORE]. Such an address may contain nearly any character from the Universal Character Set (as specified in [UCS2]) and must adhere to various profiles of [STRINGPREP]. The result is that an XMPP address is fully internationalizable and is essentially an IRI without a scheme. Therefore this memo defines an XMPP IRI scheme rather than an XMPP URI scheme, enabling applications to re-use the rules for transforming IRIs into URIs (specified in [IRI]) if needed. 1.1 Terminology This document inherits terminology described in [IRI], [URI], and [XMPP-CORE]. 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 RFC 2119 [TERMS]. 2. Description of xmpp: IRI Scheme 2.1 Rationale Many applications can be built using XMPP. As specified in [XMPP-IM], instant messaging and presence applications of XMPP must handle the im: and pres: URI schemes specified by [CPIM] and [CPP]. However, it is appropriate to define an XMPP-specific scheme for other applications of XMPP (such as network management, workflow applications, generic publish-subscribe, remote procedure calls, content syndication, gaming, and middleware) since these applications do not necessarily implement instant messaging and presence Saint-Andre Expires December 8, 2005 [Page 3] Internet-Draft XMPP-IRI June 2005 semantics. Therefore, this document defines a generic scheme that will enable applications to address as an IRI any entity that can communicate via XMPP. The xmpp: scheme is provided mainly for use by non-native interfaces and applications, and primarily for the purpose of identification rather than interaction (on the latter distinction, see Section 1.2.2 of [URI]). In order to ensure interoperability on XMPP networks, when data is routed to an XMPP entity (e.g., when an XMPP address is contained in the 'to' or 'from' attribute of an XML stanza) or an XMPP entity is otherwise identified in standard XMPP protocol elements, the entity MUST be addressed as <[node@]domain[/resource]> (i.e., without a prepended scheme), where the "node identifier", "domain identifier", and "resource identifier" portions of an XMPP address conform to the definitions provided in Section 3 of [XMPP- CORE]. (Note: For historical reasons, the term "resource identifier" is used in XMPP to refer to the optional portion of an XMPP address that follows the domain identifier and the "/" separator character (for details, refer to Section 3.4 of [XMPP-CORE]); this use of the term "resource identifier" is not to be confused with the meanings of "resource" and "identifier" provided in Section 1.1 of [URI].) 2.2 Form As described in [XMPP-CORE], an XMPP address used natively on an XMPP network is a string of Unicode characters that (1) conforms to a certain set of [STRINGPREP] profiles and [IDNA] restrictions, (2) follows a certain set of syntax rules, and (3) is encoded as [UTF-8]. The form of such an address can be represented using Augmented Backus-Naur Form ([ABNF]) as: [ node "@" ] domain [ "/" resource ] The "node" and "resource" rules rely on distinct profiles of [STRINGPREP] and the "domain" rule relies on the concept of an internationalized domain name as described in [IDNA]. In addition, it is desirable to take advantage of more advanced aspects of URI syntax and semantics in XMPP IRIs, such as authority components, query components, and fragment identifier components. Therefore, the ABNF syntax for an XMPP IRI is defined as shown in the IRI scheme syntax (Section 3.2) section of this document (see below under "IANA Registration"). (Note: There is no need to refer to punycode in the IRI syntax itself, since any punycode representation would occur only inside an XMPP application in order to represent internationalized domain Saint-Andre Expires December 8, 2005 [Page 4] Internet-Draft XMPP-IRI June 2005 names.) The following is an example of a basic XMPP IRI used for purposes of identifying a node associated with an XMPP server (an IM user is one type of such a node, but by no means the only type): xmpp:node@example.com Descriptions of the various components of an XMPP IRI are provided in the following sections. 2.3 Authority Component As explained in Section 2.8 of this memo, in the absence of an authority component the processing application would authenticate as a configured user at a configured XMPP server. The presence of an authority component (always preceded by "//") signals the processing application to authenticate as the node@domain specified in the authority component, rather than as a configured node@domain. (While it is unlikely that the authority component will be included in most XMPP IRIs, the scheme allows for its inclusion if appropriate.) Thus, the following XMPP IRI indicates to authenticate as "guest@example.com": xmpp://guest@example.com Note well that this is quite different from the following XMPP IRI, which identifies a node "guest@example.com" but does not signal the processing application to authenticate as that node: xmpp:guest@example.com Similarly, using a possible query component of "?message" to trigger an interface for sending a message, the following XMPP IRI signals the processing application to authenticate as "guest@example.com" and send a message to "support@example.com": xmpp://guest@example.com/support@example.com?message By contrast, the following XMPP IRI signals the processing application to authenticate as its configured default account and send a message to "support@example.com": xmpp:support@example.com?message Saint-Andre Expires December 8, 2005 [Page 5] Internet-Draft XMPP-IRI June 2005 2.4 Path Component The path component of an XMPP IRI identifies an XMPP address or specifies the XMPP address to which an XML stanza shall be directed at the end of IRI processing. For example, the following XMPP IRI identifies a node associated with an XMPP server: xmpp:random-node@example.com The following XMPP IRI identifies a node associated with an XMPP server along with a particular XMPP resource identifier associated with that node: xmpp:random-node@example.com/some-resource Inclusion of a node is optional in XMPP addresses, so that the following XMPP IRI simply identifies an XMPP server: xmpp:example.com 2.5 Query Component There are many potential use cases for encapsulating information in the query component of an XMPP IRI; examples include but are not limited to: o Sending an XMPP message stanza (see [XMPP-IM]). o Adding a roster item (see [XMPP-IM]). o Sending a presence subscription (see [XMPP-IM]). o Probing for current presence information (see [XMPP-IM]). o Joining an XMPP-based text chat room (see [JEP-0045]). o Registering with another entity (see [JEP-0077]). o Triggering a remote procedure call (see [JEP-0009]). o Providing a SOAP interface (see [JEP-0072]). o Discovering the identity or capabilities of another entity (see [JEP-0030]). o Interacting with publish-subscribe channels (see [JEP-0060]). Many of these potential use cases are application-specific, and the full range of such applications cannot be foreseen in advance given the continued expansion in XMPP development; however, there is agreement within the Jabber/XMPP developer community that all of the uses envisioned to date can be encapsulated via a "query type", optionally supplemented by one or more "key-value" pairs (this is similar to the "application/x-www-form-urlencoded" MIME type Saint-Andre Expires December 8, 2005 [Page 6] Internet-Draft XMPP-IRI June 2005 described in [HTML]). As an example, an XMPP IRI intended to launch an interface for sending a message to the XMPP entity "random-node@example.com" might be represented as follows: xmpp:random-node@example.com?message Similarly, an XMPP IRI intended to launch an interface for sending a message to the XMPP entity "random-node@example.com" with a particular subject might be represented as follows: xmpp:random-node@example.com?message;subject=Hello%20World If included, the query component MUST first be encoded as a [UTF-8] string. If the processing application does not understand query components, it MUST ignore the query component and treat the IRI as consisting of, for example, rather than . If the processing application does not understand a particular key within the query component, it MUST ignore that key and its associated value. In pursuit of interoperability, it may be valuable to maintain a registry of query types and perhaps even of keys for use in the query component portion of XMPP IRIs. Given that such values will most likely be specific to particular applications of XMPP rather than core to XMPP itself, it seems reasonable that such a registry, if created, would be maintained by the Jabber Registrar function of the Jabber Software Foundation as described in [JEP-0053], rather than by the IANA. A proposal for creating such a registry can be found in [JEP-0147]. 2.6 Fragment Identifier Component As stated in Section 3.5 of [URI], "The fragment identifier component of a URI allows indirect identification of a secondary resource by reference to a primary resource and additional identifying information." Because the resource identified by an XMPP IRI does not make available any media type (see [MIME]) and therefore (in the terminology of [URI]) no representation exists at an XMPP resource, the semantics of the fragment identifier component in XMPP IRIs are to be "considered unknown and, effectively, unconstrained" (ibid.). Particular XMPP applications MAY make use of the fragment identifier component for their own purposes. However, if a processing application does not understand fragment identifier components or the syntax of a particular fragment identifier component included in an Saint-Andre Expires December 8, 2005 [Page 7] Internet-Draft XMPP-IRI June 2005 XMPP IRI, it MUST ignore the fragment identifier component. If included, the fragment identifier component MUST first be encoded as a [UTF-8] string. 2.7 Generation of XMPP IRIs 2.7.1 IRI Generation Method In order to form an XMPP IRI from an XMPP node identifier, domain identifier, and resource identifier, the generating application MUST concatenate: 1. the "xmpp:" scheme 2. optionally (if an authority component is to be included), the characters "//", an authority component of the form node@domain, and the character "/" 3. optionally (if the XMPP address contained an XMPP "node identifier"), a string of Unicode characters that conforms to the "nodeid" rule, followed by the "@" character 4. a string of Unicode characters that conforms to the "ihost" rule 5. optionally (if the XMPP address contained an XMPP "resource identifier"), the character "/" and a string of Unicode characters that conforms to the "resid" rule 6. optionally (if a query component is to be included), the "?" character and query component 7. optionally (if a fragment identifier component is to be included), the "#" character and fragment identifier component 2.7.2 IRI Generation Example Consider the following XMPP address: (Note: The string "ř" stands for the Unicode character LATIN SMALL LETTER R WITH CARON and the string "č" stands for the Unicode character LATIN SMALL LETTER C WITH CARON, following the "XML Notation" used in [IRI] to represent characters that cannot be rendered in ASCII-only documents. The '<' and '>' characters are not part of the address itself, but are provided to set off the address for legibility. For those who do not read Czech, this example could be Anglicized as "george@czech-lands.example/In Prague".) In accordance with the process specified above, the generating application would do the following to generate a valid XMPP IRI from this address: Saint-Andre Expires December 8, 2005 [Page 8] Internet-Draft XMPP-IRI June 2005 1. Ensure that the XMPP address conforms to the rules specified in [XMPP-CORE], including application of the relevant [STRINGPREP] profiles and encoding as a [UTF-8] string. 2. Concatenate the following: 1. the "xmpp:" scheme 2. an "authority component" if included (not shown in this example) 3. a string of Unicode characters that represents the XMPP address 4. the "?" character followed by a "query component" if appropriate to the application (not shown in this example) 5. the "#" character followed by a "fragment identifier component" if appropriate to the application (not shown in this example) The result is this XMPP IRI: 2.8 Processing of XMPP IRIs 2.8.1 IRI Processing Method In order to decompose an XMPP IRI, a processing application MUST separate: 1. the "xmpp:" scheme 2. optionally (if the XMPP IRI contains an authority component), the authority component (the string of US-ASCII characters between the "//" characters and the first "/" character or the end of the IRI) 3. a string of Unicode characters that represents an XMPP address 4. optionally the query component (if any), using the "?" character as a separator 5. optionally the fragment identifier component (if any), using the "#" character as a separator At this point, the processing application would either (1) complete further XMPP handling itself or (2) invoke a helper application to complete XMPP handling; such XMPP handling would most likely consist of the following steps: 1. Authenticating either as the user specified in the authority component or as the configured user at the configured XMPP server if not already so authenticated. Saint-Andre Expires December 8, 2005 [Page 9] Internet-Draft XMPP-IRI June 2005 2. Optionally determining the nature of the intended recipient (e.g., via [JEP-0030]). 3. Optionally presenting an appropriate interface to a user based on the nature of the intended recipient and/or the contents of the query component. 4. Generating an XMPP stanza that translates any user or application inputs into their corresponding XMPP equivalents. 5. Sending the XMPP stanza via the authenticated server connection for delivery to the intended recipient. Note: It may help implementors to note that the first two steps of "further XMPP handling" are similar to HTTP authentication ([HTTP- AUTH]), while the next three steps are similar to the handling of mailto: URIs ([MAILTO]). 2.8.2 IRI Processing Example Consider the XMPP IRI that resulted from the previous example: In accordance with the process specified above, the processing application would remove the "xmpp:" scheme to extract the XMPP address from this XMPP IRI. The result is this XMPP address: 2.9 Internationalization Because XMPP addresses are [UTF-8] strings and because the non-US- ASCII octets in XMPP addresses can be easily converted to percent- encoded octets, XMPP addresses are designed to work well with Internationalized Resource Identifiers ([IRI]). In particular, with the exception of stringprep verification and the conversion of syntax-relevant US-ASCII characters (e.g., "?"), an XMPP IRI can be constructed directly by prepending "xmpp:" to an XMPP address. 3. IANA Registration of xmpp: IRI Scheme This section provides the information required to register the xmpp: IRI scheme. 3.1 IRI scheme name xmpp Saint-Andre Expires December 8, 2005 [Page 10] Internet-Draft XMPP-IRI June 2005 3.2 IRI scheme syntax The syntax for an xmpp: IRI is defined below using Augmented Backus- Naur Form as specified by [ABNF]. (The "ifragment", "ihost", and "iunreserved" rules are defined in [IRI]; the "pct-encoded" and "sub- delims" rules are defined in [URI].) xmppiri = "xmpp:" hier-xmpp [ "?" querycomp ] [ "#" ifragment ] hier-xmpp = authpath / path-xmpp authpath = "//" auth-xmpp [ "/" path-xmpp ] auth-xmpp = nodeid "@" ihost path-xmpp = [ nodeid "@" ] ihost [ "/" resid ] nodeid = *( iunreserved / pct-encoded / nodeallow ) nodeallow = "!" / "$" / "(" / ")" / "*" / "+" / "," / ";" / "=" / "^" / "`" / "{" / "|" / "}" resid = *( iunreserved / pct-encoded / sub-delims ) querycomp = querytype [ *pair ] querytype = *iunreserved pair = ";" key "=" value key = *iunreserved value = *( iunreserved / pct-encoded ) 3.3 Character encoding considerations Prior to any conversion into a IRI and in accordance with [XMPP- CORE], an Extensible Messaging and Presence Protocol (XMPP) address MUST be represented as [UTF-8] by the generating application (e.g., by transforming an application's internal representation of the address as a UTF-16 string into a UTF-8 string). The UTF-8 string MUST then be prepended with an xmpp: scheme. 3.4 Intended usage The xmpp: IRI identifies entities that natively communicate using the Extensible Messaging and Presence Protocol (XMPP), and is mainly used for identification rather than processing. However, an application that processes an xmpp: IRI SHOULD reconstruct the encapsulated XMPP address, authenticate with the appropriate XMPP server, and send an appropriate XMPP "stanza" (XML fragment) to the XMPP address. There is no MIME type associated with this IRI. 3.5 Applications and/or protocols which use this scheme name The xmpp: IRI is intended to be used by interfaces to an XMPP network from non-native user agents such as web browsers, as well as by non- native applications that need to identify XMPP entities as full IRIs. Saint-Andre Expires December 8, 2005 [Page 11] Internet-Draft XMPP-IRI June 2005 3.6 Security considerations See Security Considerations (Section 5) of XXXX. 3.7 Relevant publications [XMPP-CORE] 3.8 Person and email address to contact for further information Peter Saint-Andre [mailto:stpeter@jabber.org] 3.9 Author/change controller This scheme is registered under the IETF tree. As such, the IETF maintains change control. 4. IANA Considerations This document registers a IRI scheme. The registration template can be found in Section 3 of this document. 5. Security Considerations The security considerations discussed in [URI], [IRI] , and [XMPP- CORE] apply to XMPP IRIs. Providing an interface to XMPP services from non-native applications introduces new security concerns. For example, the ability to interact with XMPP entities via a web browser may expose sensitive information to attacks that are not possible or that are unlikely on a native XMPP network. Due care must be taken in deciding what information is appropriate for representation in XMPP IRIs. Care must also be taken in exposing XMPP addresses in the authority and path components of XMPP IRIs that are publicly accessible. 6. References 6.1 Normative References [ABNF] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [IRI] Duerst, M. and M. Suignard, "Internationalized Resource Identifiers (IRIs)", RFC 3987, January 2005. [TERMS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. Saint-Andre Expires December 8, 2005 [Page 12] Internet-Draft XMPP-IRI June 2005 [UCS2] International Organization for Standardization, "Information Technology - Universal Multiple-octet coded Character Set (UCS) - Amendment 2: UCS Transformation Format 8 (UTF-8)", ISO Standard 10646-1 Addendum 2, October 1996. [URI] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, January 2005. [UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003. [XMPP-CORE] Saint-Andre, P., "Extensible Messaging and Presence Protocol (XMPP): Core", RFC 3920, October 2004. 6.2 Informative References [CPIM] Peterson, J., "Common Profile for Instant Messaging (CPIM)", RFC 3860, August 2004. [CPP] Peterson, J., "Common Profile for Presence (CPP)", RFC 3859, August 2004. [HTML] Raggett, D., "HTML 4.0 Specification", W3C REC REC-html40- 19980424, April 1998. [HTTP-AUTH] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S., Leach, P., Luotonen, A., and L. Stewart, "HTTP Authentication: Basic and Digest Access Authentication", RFC 2617, June 1999. [IDNA] Faltstrom, P., Hoffman, P., and A. Costello, "Internationalizing Domain Names in Applications (IDNA)", RFC 3490, March 2003. [IMP-MODEL] Day, M., Rosenberg, J., and H. Sugano, "A Model for Presence and Instant Messaging", RFC 2778, February 2000. [IMP-REQS] Day, M., Aggarwal, S., and J. Vincent, "Instant Messaging / Presence Protocol Requirements", RFC 2779, February 2000. [JEP-0009] Saint-Andre Expires December 8, 2005 [Page 13] Internet-Draft XMPP-IRI June 2005 Adams, D., "Jabber-RPC", JSF JEP 0009, December 2002. [JEP-0030] Hildebrand, J., Millard, P., Eatmon, R., and P. Saint- Andre, "Service Discovery", JSF JEP 0030, March 2005. [JEP-0045] Saint-Andre, P., "Multi-User Chat", JSF JEP 0045, April 2005. [JEP-0053] Saint-Andre, P., "Jabber Registrar", JSF JEP 0053, May 2004. [JEP-0060] Millard, P., Saint-Andre, P., and R. Meijer, "Publish- Subscribe", JSF JEP 0060, March 2005. [JEP-0072] Forno, F. and P. Saint-Andre, "SOAP Over XMPP", JSF JEP 0072, April 2005. [JEP-0077] Saint-Andre, P., "In-Band Registration", JSF JEP 0077, August 2004. [JEP-0147] Saint-Andre, P., "XMPP URI Query Components", JSF JEP 0147, June 2005. [MAILTO] Hoffman, P., Masinter, L., and J. Zawinski, "The mailto URL scheme", RFC 2368, July 1998. [MIME] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996. [NAMEPREP] Hoffman, P. and M. Blanchet, "Nameprep: A Stringprep Profile for Internationalized Domain Names (IDN)", RFC 3491, March 2003. [STRINGPREP] Hoffman, P. and M. Blanchet, "Preparation of Internationalized Strings ("STRINGPREP")", RFC 3454, December 2002. [URL-GUIDE] Saint-Andre Expires December 8, 2005 [Page 14] Internet-Draft XMPP-IRI June 2005 Masinter, L., Alvestrand, H., Zigmond, D., and R. Petke, "Guidelines for new URL Schemes", RFC 2718, November 1999. [URL-REG] Petke, R. and I. King, "Registration Procedures for URL Scheme Names", BCP 35, RFC 2717, November 1999. [US-ASCII] American National Standards Institute, "Coded Character Set - 7-bit American Standard Code for Information Interchange", ANSI X3.4, 1986. [XMPP-IM] Saint-Andre, P., "Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence", RFC 3921, October 2004. Author's Address Peter Saint-Andre Jabber Software Foundation Email: stpeter@jabber.org Saint-Andre Expires December 8, 2005 [Page 15] Internet-Draft XMPP-IRI June 2005 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. 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Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The Internet Society (2005). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Saint-Andre Expires December 8, 2005 [Page 16]