Publish-Subscribe (XEP-0060)  nodes are commonly used by XMPP users to subscribe to news feeds. This document describe a way, for them, to share some of the nodes to which they have subscribed with other users.
The list of Publish-Subscribe (XEP-0060)  subcribed nodes is stored on a classic Personal Eventing Protocol (XEP-0163)  node qualified by the 'urn:xmpp:subscription' namespace. If an entity wishes to make pubsub subscriptions publicly available then the entity MAY publish them on this node. The entity SHOULD ensure that this information is kept up to date.
Information about the subscribed node is provided by the user client. The subscription container is defined as a classic <subscription/> element with theses specific constraints :
|server||attribute||Any server's address||REQUIRED|
The aim of this XEP is to handle a list of subscriptions. To simplify the managment of this list the ID of the Publish-Subscribe (XEP-0060)  items MUST be generated according to the following method :
The motivations for this document are to :
The title element of a <subscription/> item SHOULD be in the same language as the contents of the node in question.
The publication of user tune information is not known to introduce any new security considerations above and beyond those defined in XEP-0060: Publish-Subscribe.
This document requires no interaction with the Internet Assigned Numbers Authority (IANA) .
The XMPP Registrar  is requested to issue an initial namespace of "urn:xmpp:pubsub:subscription".
REQUIRED for protocol specifications.
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The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 6120) and XMPP IM (RFC 6121) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.
The primary venue for discussion of XMPP Extension Protocols is the <firstname.lastname@example.org> discussion list.
Discussion on other xmpp.org discussion lists might also be appropriate; see <http://xmpp.org/about/discuss.shtml> for a complete list.
Errata can be sent to <email@example.com>.
The following requirements keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".
3. The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>.
4. The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <https://xmpp.org/registrar/>.
Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/
Initial published version approved by the XMPP Council.