In the attached document, I have provided some “use cases” that make use of defined (and implemented) capabilities of the DNS in order to find out about a person or organization’s interaction/collaboration capabilities (including endpoint information). The use cases are annotated with hints about how the Dynamic Delegation Discovery Service [DDDS -- Dynamic Delegation Discovery Service, whose core parts are specified in five RFCs 3401 through 3405] could be used in building a DDDS application -- the sequence of processing steps involved when using several DNS queries to produce a desired discovery result. Defining a (reasonably simple but complete) DDDS application allows us to generalize the discovery/location aspects of PEPPOL to apply to a much wider range of interactions, and to support a much wider range of security options. Specific DDDS applications are found in VOIP, SIP, ONS, FONS and several other specifications. Also I have included a brief terminology section that we can add to the wiki. More additions will be needed. Attachment: Metadata Service Location using DDDS facilities.docx Description: Metadata Service Location using DDDS facilities.docx