Handle System Workshop System Updates Laurence Lannom 21 June 2007 Corporation for National Research Initiatives Reston, VA

Corporation for National Research Initiatives Berkeley DB JE support –Increased performance –Increased scalability Template resolution, aka virtual handles –All handles that match a given pattern, e.g., 123/456*, will resolve to the same data, e.g., a single URL at which all objects are found –Currently a fixed value per pattern, but could be extended to be a function of the handle presented for resolution (think limited regular expressions), e.g., 123/456.abc, resolved by any client, would resolve to the pattern and the server would return New Features in Upcoming Releases Server Side

Corporation for National Research Initiatives Choose by facility - currently being deployed in the proxy service –Pack alternatives into a single handle value using XML –Include criteria for selecting among them, to be evaluated by the client –Example: alternatives = geographic locations, criteria = incoming IP, proxy matches incoming IP to IP tables and picks best location, other clients could be configured to select country in some other way. –For some handle, the value of type CNRI.RSRC_LOC New Features in Upcoming Releases Client Side

Corporation for National Research Initiatives Extended Handle client library to provide higher level API –Creation: handleValue = hsClient.createHandleValue(1,URL," hsClient.createHandle(handle, new HandleValue[] {handleValue}); –Deletion: hsClient.deleteHandle(handle); Resolver.xml –Local file containing override or default values for specific handles If override, local client never goes to handle system for that handle, but just uses the given value If default, local client uses that value if it cannot resolve the handle for whatever reason, e.g., on an airplane Web services interface to HS at multiple levels – Added to current set of proxies –Released as a stand-alone interface that could employed by other organizations as needed Handle plug-in for Acrobat Reader re-released for Reader 8 New Features in Upcoming Releases Client Side

Corporation for National Research Initiatives Handle Records may be thought of as sets of handle triples: handle:type:value Clients rely on types in order to interpret the values All of this is transparent to HS servers - they simply store and deliver type:value pairs - type is completely open, no type police A few standard types –Admin types - what the HS itself needs to operate –Common types, e.g., URL –Registered as handles, e.g., 0.TYPE/URL Lots of projects using the HS invent types for their own purposes Two issues coming to the fore –What can a client do with a type it doesnt know about ahead of time? –What sort of synergies across projects are we missing through wheel re- invention? The Issue of Handle Types (Not Types of Handles)

Corporation for National Research Initiatives Keep the 0.TYPE mechanism in place Encourage registration, with low barriers –Is it in use? –Is it understandable? –Is it harmful to the overall HS? Expand the required type/values under the 0.TYPE handle –Human-readable description –Responsible party –Dates of creation and last revision –Related handle types –Searchable registry in which the type is registered Introduce a searchable Registry of Handle Types –Publicly available for searching –Searchable version of the complete set of 0.TYPE records –Added fields and examples? Issues –Ontologies: are two types really the same but using different descriptions or languages? –Trial vs accepted types Proposed Registry of Handle Types