Service Discovery Extensions (XEP-0128)  defines a way for an XMPP entity to include extended information in its responses to Service Discovery (XEP-0030)  information requests. This document specifies a usage of XEP-0128 whereby an XMPP entity can provide detailed data about itself in such responses. This protocol is intended to replace Software Version (XEP-0092)  for software information discovery (thus reducing or eliminating the need for distinct software version requests) and also provides a format that can be encapsulated into Entity Capabilities (XEP-0115)  notifications.
To illustrate this usage, consider the following example of a disco#info request-response interaction that includes detailed client information:
Upon receiving the disco#info request, the software replies and includes extended information in a data form (Data Forms (XEP-0004) ), where the icon is communicated using the format defined in Data Forms Media Element (XEP-0221) .
The fields have the following meaning:
Service discovery information is typically world-readable. Therefore, care should be taken in exposing information that may make it easier for a potential attacker to target the publishing entity's system (e.g., the operating system on which the software is running).
This document requires no interaction with the Internet Assigned Numbers Authority (IANA) .
The XMPP Registrar  shall include the following information in its registries.
Field Standardization for Data Forms (XEP-0068)  defines a process for standardizing the fields used within Data Forms qualified by a particular namespace, and XEP-0128 describes how to use field standardization in the context of service discovery. This section registers fields for software information scoped by the "urn:xmpp:dataforms:softwareinfo" FORM_TYPE.
Thanks to Dave Cridland, Olivier Goffart, Joe Hildebrand, Etan Reisner, Remko Tronçon, and Jiří Zárevúcký for their comments.
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Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/
Per Last Call feedback, removed icons for presence states; redefined the icon field to use media element per XEP-0221.
Added icon fields.
Initial published version.
Added software field; generalized to be software information, not client information.
Clarified relationship to Software Version (XEP-0092).