[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [Elist Home]
Subject: [ubl-ndrsc] Fwd: The Only Hard Problem in XML
Too true! >-------- Original Message -------- >From: XML_in_Practice@itw.itworld.com >Subject: The Only Hard Problem in XML >To: "steve trezise" <steven.trezise@sun.com> > > > >XML IN PRACTICE --- January 24, 2002 >Published by ITworld.com -- changing the way you view IT >http://www.itworld.com/newsletters >________________________________________________________________________________ > >HIGHLIGHTS > >* The harder we try to establish a hierarchical IT naming structure, > the more untamable the task becomes. >________________________________________________________________________________ > > >The Only Hard Problem in XML >By Sean McGrath > >Before I start, in the grandest tradition of us XML types, let me >generalize. This article is about the only hard problem in computing in >general -- never mind just XML. And that problem is? > >Naming things. > >These two simple words, added together spell trouble all over the IT >landscape. On your network you have files; files have names. You put >them in folders that have names, on drives that have names. All the >resources on the network are named at least once and probably twice -- >once with a human friendly name, like foo.baz.com, and once with a >computer friendly name, like http://194.125.145.37. > >Names contain hierarchical layers, which is where the trouble starts. >With DNS, some top-level domain names where created: .COM, .ORG, etc. >These, in turn, break into sub-domains and so on. IP addresses split >into segments separated by periods and various routing techniques rely >on being able to peel off various layers from the segments. > >The thing about naming conventions is that they are self limiting. >Creating one involves taking a view of the world of discourse, >classifying it into a hierarchy of "things" that have names, and >joining the name segments into longer names. In a word: taxonomies. > >"Taxonomy" is a great word to describe the naming problem because it >covers both giving things names and putting them into some sort of >classification system. We can see taxonomy problems everywhere: the >Domain Name Service, Carl Linnaeus's organization of plant species, >Niels Bohr's model of the atom, etc.... > >And so to XML. XML is all about taxonomy problems. Every time we >concoct a schema -- whatever the notation -- we are addressing the >naming problem and creating a taxonomy. Every time we seek to >interchange XML data with someone, we need to address the naming >problem. Their data may overlap with yours in terms of its true meaning >(that dreaded word "semantics") but if their system has grown up >independently of yours, it almost certainly uses a different naming >system. > >The blue sparks that fly out of XML people's ears when you put them >into a room together are due, in no small part, to naming problems. The >great holy grail of interchange is to be able to interchange the >meaning of information, in XML form, without the enormous overhead in >time and money of industry standard schemas and/or point-to-point XML >transformations. > >Tim Berners-Lee's vision of the Semantic Web has caused some XML >people, me included, to say, "Good. Maybe now the world will see the >enormous nature of this naming knowledge problem." Note that we did not >shout, "Yippee. A solution cometh!" > >This problem is hard, real hard. It is hard because it requires caging >a wild animal called "knowledge". Nobody knows how to do that. Wrapping >angle-bracketed tags around data does not magically transform it into >knowledge. Knowledge refuses to be written down. It is not "declarable" >in any syntax, XML included. It remains in the minds of people, >transferred transiently and at much cost into computer programs. > >The field of "naming things" -- variously referred to as mereology, >ontology, epistemology, data modeling, RDF, Topic Maps, Meta- >Architectures -- is fascinating to watch. Much work goes into coming up >with ways to express the knowledge hidden in hierarchies, yet that >knowledge itself is not hierarchical, which makes humans' quest to make >it so all the more puzzling. > >Perhaps the problem is unsolvable. Perhaps, thanks to the Godelian >insight into the incompleteness of knowledge of any field, we petty >humans cannot hope to write down the knowledge inherent in the "system" >to which we are a part. Which isn't to say we should give up of course, >but such musings can help keep you sane when your day job revolves >around grinding out naming conventions for XML schemas and XSLT >transformations to change data from one naming convention to another. > >About the author(s) >------------------- >Sean McGrath is CTO of Propylon. He is an internationally acknowledged >authority on XML and related standards. He served as an invited expert >to the W3C's Expert Group that defined XML in 1998. He is the author of >three books on markup languages published by Prentice Hall. >________________________________________________________________________________ > >ADDITIONAL RESOURCES > >Naming Things >http://itw.itworld.com/GoNow/a14724a51108a103396130a3 > >Carl Linnaeus >The father of modern plant and animal classification (1707-1778) >http://itw.itworld.com/GoNow/a14724a51108a103396130a1 > >Godel's Incompleteness Theorem >http://itw.itworld.com/GoNow/a14724a51108a103396130a4 > >Semantic Web >http://itw.itworld.com/GoNow/a14724a51108a103396130a6 > >The Semantic Web: A Primer >http://itw.itworld.com/GoNow/a14724a51108a103396130a2 > >The Semantic Web: An Introduction >http://itw.itworld.com/GoNow/a14724a51108a103396130a5 >________________________________________________________________________________ > >ITWORLD.COM NEWSLETTER ARCHIVE > >Index of XML in Practice >http://www.itworld.com/nl/xml_prac/ > >SOAP: Simple Object Access Protocol >http://www.itworld.com/nl/xml_prac/06072001/ > >Vendors Stock the Java Toolbox >http://www.itworld.com/nl/xml_prac/06142001/ >________________________________________________________________________________ > >CUSTOMER SERVICE > >SUBSCRIBE/UNSUBSCRIBE: >- Go to: http://www.itworld.com/newsletters >- Click on "View my newsletters" to log in and manage your account >- To subscribe, check the box next to the newsletter >- To unsubscribe, uncheck the box next to the newsletter >- When finished, click submit > >Questions? Please e-mail customer service at: mailto:support@itworld.com >________________________________________________________________________________ > >CONTACTS > >* Editorial: Andrew Santosusso, Newsletter Editor, > andrew_santosusso@itworld.com >* Advertising: Clare O'Brien, Vice President of Sales, > clare_obrien@itworld.com >* Career Corner: Janis Crowley, Vice President/General Manager, IDG > Recruitment Solutions, janis_crowley@itcareers.net >* Other inquiries: Jodie Naze, Senior Product Marketing Manager, > jodie_naze@itworld.com > >________________________________________________________________________________ > >PRIVACY POLICY > >ITworld.com has been TRUSTe certified >http://www.itworld.com/Privacy/ > >Copyright 2002 ITworld.com, Inc., All Rights Reserved. >http://www.itworld.com > > > > >**SEND TO A FRIEND** >Share this email with a friend! Click here! >http://itw.itworld.com/GoForward/a14724a51108aSa103396130a39 > >SUBSCRIBE/UNSUBSCRIBE >Please click on the link below to modify your subscription, unsubscribe, >or change your email address: > >http://itw.itworld.com/Change-Remove/a14724a103396130a39a51108 -- Eve Maler +1 781 442 3190 Sun Microsystems XML Technology Center eve.maler @ sun.com
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [Elist Home]
Powered by eList eXpress LLC