Thursday, October 4, 2007

VTLS Visualizer issues

One of the things to consider when picking a repository is the roadmap for the application. Here's a post I sent to the ARROW group (Australian Research Repositories Online to the World) on one level it's a VITAL users group, but it's also a lot more than that.

In summary I'm saying that it looks like the new VTLS Visualizer product looks like a really good idea, but I am concerned about the upgrade path between current VITAL repositories and the new approach used by Visualizer.

(From an AANRO perspective it's worth nothing that Visualizer does nothing to address the lack of a web based interface where non-technical users can input and edit Fedora objects.)

At the end are some as-yet unanswered questions for VTLS, the company behind VITAL.

At the ARROW community day last week Vinod Chachra demonstrated Visualizer - a new portal product which I believe is based on Apache Solr, which in turn is based on the Apache Lucene search library. With more than a million records it performed very well, at least in the demo.

Like VITAL, Visualizer offers faceted searching. I was intrigued to see that it also has some kind of ontology feature - it was able to work out that Scotland is part of the UK (or was it Europe?), I forget what Vinod called this, but it looks like you can set up hierarchies for various fields in the index and have the portal show the relationships. We have discussed this very feature at USQ as part of our work on the Fred project and a proof-of-concept Solr portal that David Levy and Oliver Lucido are writing, and we think that this will perform better than an RDF collections based approach as used in the current VITAL. The other advantage of this technology is that setting up a new subject based portal or restricting access is as simple as appending a query to every search.

Vinod confirmed at the meeting that Visualizer will eventually become the portal application for VITAL so it will be important to start planning for this now. I also got the impression from talking to him that some of the same technologies will be used in VITAL, starting with the forthcoming version 4, which is quite different from what Heather told us at the last ARROW development group.

Here are some questions for VTLS:

  1. If we use Communities and Collections in VITAL will these transfer to VITAL 4 & Visualizer? (RUBRIC central recommends NOT using collections, by the way)

  2. Will the new Consortium (portal) support in VITAL 4 transfer to Visualizer?

  3. Can the ontologies used by Visualizer be used as authority control for VITAL/VALET?

  4. What kinds of indexing technologies will be used by VITAL 4 (RDF? Lucene? A proprietary database?)

It is important for the user community to ask these questions now. Remember that when VITAL 3 was released it was several weeks before VTLS released software to migrate VITAL 2 repositories to VITAL 3. A well tested migration path is an essential part of any product roadmap.

(In my judgment Visualizer will provide a much more flexible and scalable platform for repository portals than the current VITAL architecture so I support this development if the transition can be managed effectively. )

Copyright 2007 The University of Southern Queensland

Content license: Creative Commons Attribution-ShareAlike 2.5 Australia.

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