Hi,
We are working on this issue with our DSNotify [1] approach. Our
solution is based on indexing subgraphs of available
LD graphs and deriving feature vectors (FV) for each indexed resource.
By comparing the sets of newly detected,
recently removed and indexed FVs, we can detect create, remove, update
and "move" [2] events in LD sources. These
events are logged and can be accessed via a Java API, an XML-RPC
interface, and an HTTP interface.
We are also developing a vocabulary (and a corresponding API) that can
be used to describe so-called eventsets: sets of events that
occurred in a particular data source. This vocab is based on LODE and
SCOVO and a first draft will be published soon
on our website.
But DSNotify is not ready to index the whole Web of Data. It may rather
be used as an add-on for particular data providers that
want to keep a high level of link integrity in their data (because the
reported events may be used by the data provider to update
its hosted data/links).
Other related approaches:
- Triplify's Linked Data Up-date Log [3]
- Silk's Web of Data Link Maintenance Protocol [4]
best regards,
Niko
[1] http://dsnotify.org/
[2] The main purpose of DSNotify is to detect "move" events in data
sources, i.e., when resources are published with different identifiers
(e.g., under a
different HTTP URI). Although this should not be the case theoretically
(URIs should be "cool") it happens quite often in reality, see our paper
for details.
[3] http://triplify.org/vocabulary/update
[4] http://www4.wiwiss.fu-berlin.de/bizer/silk/wodlmp/
Georgi Kobilarov wrote:
Hi all,
I'd like to start a discussion about a topic that I think is getting
increasingly important: RDF update feeds.
The linked data project is starting to move away from releases of large data
dumps towards incremental updates. But how can services consuming rdf data
from linked data sources get notified about changes? Is anyone aware of
activities to standardize such rdf update feeds, or at least aware of
projects already providing any kind of update feed at all? And related to
that: How do we deal with RDF diffs?
Cheers,
Georgi
--
Georgi Kobilarov
www.georgikobilarov.com