While working on a project for my day job, I cautioned against blind recitation of the publish-find-bind mantra and was asked for an alternative. This followed our discussion of Danny's visibility write-up and so I scratched down some thoughts and exchanged a few emails with Danny for a sanity check. Below is a capture of our exchange and the attached (apologies for the length) are the ideas as they stand after incorporating some (but not all) of the discussion.
(Sorry for the Word attachment but (1) wasn't sure where to put it in the wiki and (2) it's too late to fool around with uploading and positioning figures. Can remedy later.)
The email capture follows. As typical, read from the bottom up.
I concur with your distinction between global and groups. It also does a nice job of mentioning taxonomies. You have captured the two forms of global visibility that I would expect to see the architecture discuss. While an "aggregate of information expressed in many vocabularies and categorized using many taxonomies" is likely to be the more prevalent type of visibility in a global SOA, significant efforts are being made for the GIG architecture to "mediate capabilities that enable discoveries across vocabularies" as well as classification levels.
Thanks for the quick feedback. What I sent was somewhat of a ramble and a capture of thoughts without things completely worked out, without a clear idea of what points needed to be made, without a clear idea of how and/or where it eventually needs to be incorporated. My following comments continue in that tradition :-)
Global could certainly be looked at as a dynamic group of groups. I am (and I'm sure most other people are too) uncertain to what extent there will be significant content generated specifically for global, so I'm not sure I'd characterize it exclusively as a group of groups. However, that raises a possibly interesting distinction. As a group of groups, global will be an aggregate of information expressed in many vocabularies and categorized using many taxonomies (or other representations). Thus, either a global registry search will be akin to a search of the group(s) using that vocabulary and taxonomy (effectively, a search over a very small part of the entire registry content) or the global registry will have to incorporate significant mediation capabilities to enable discovery across vocabularies. I think this could be a useful distinction between group and global and a driver for use of the global registry. Figuring out how it would be appropriate to express this will be a challenge and will require more thought.
Note, I think personal, group, and global somewhat align with simple, complex, and mediated, and those categories probably influenced my thinking but I was toying with concepts without
trying to specifically match anything else. No matter what the categorization, I think the boundaries may be fuzzy so, for example, three people can jointly maintain a personal catalog without fully being a group and three groups could work together without getting to global. As we proceed I expect the boundaries to either become more clear or get permanently fuzzy.
The initial focus on UDDI and Web services had a lot to do with the actual work discussion that got me to start writing this down. I agree that it needs to be expanded beyond UDDI but that is the prevalent straw man and somehow needs direct attention because I think the UDDI structure exacerbates the registry problem. Again, this was in no way meant to be complete and your comments are valid. Again more thought is needed both on scope and presentation.
On Jul 12, 2006, at 3:06 AM, Danny Thornton wrote:
The personal, group, and global categories make sense within the context of your document. I can see how group can always imply some type of ownership domain. The question I ask myself is if global is another type of group. If global is distinguished as a dynamic ecosystem of groups, then that would make sense to me.
It would certainly be easy to integrate personal, group, and global levels into the simple, complex, and mediated sections of Visibility. I currently have one and two liner examples equivalent to the personal, group, and global examples. Your examples could be substituted for those one and two liner examples.
The beginning of your document focuses on UDDI, WSDL, and Web Services. I would also incorporate discussions about ebXML, the Process Model, and repositories. See