The Open Archives Initiative Story Thomas Krichel http://openlib.org/home/krichel Uni. of Surrey, Hitotsubashi Uni., Long Island Uni.
About this talk Follows essentially a historical approach mixes in a few digital library concepts, interrupt me if you do not get some of them does not represent an official statement botches together various ideas from different people benefited from funding by DLF, LANL, CLIR, JISC, DINI
UPS call 1999-07 Ginsparg, Luce and Van de Sompel The purpose of this call is the mobilisation of a core group to work towards achieving a universal service for author-archived literature emphasis on a pragmatic level of interoperability
UPS protoproto By Krichel, Nelson and Van de Sompel found that the main problems of interoperability between eprint initiative are –poor metadata –no uniform identifier structure –unclear legal terms and conditions –lack of selective harvesting
Santa Fe meeting 1999-10 Representatives of arXiv, cogprints, Highwire, NCSTRL, NDLTD, RePEc, SLAC/SPIRES and others chaired by Lynch and Waters sponsored by CLIR, LANL and SPARC
basic concepts Managed or formal e-print archive; not papers on the web Open e-print archive means that there is a machine interface record can be metadata or metadata & full text archive may be partitioned
business model Inspired by RePEc initiative Separation between data providers and service providers Many archives Many metadata collections Many services
requirements & realisations Metadata harvesting (not distributed database) Namespace mandatory metadata & parallel sets acceptable use registration OA Dienst subset full id=archive|record OAMS and XML transport gentlepersons agreement in a provider statement primitive templates
technical model Subset of Dienst protocol used by NCSTRL Compatible archive respond to 4 requests –List-Partitions –List-Meta-Formats –List-Contents (partitionspec, file-after, meta-format) –Disseminate (fullID, meta-format, content- type)
mandatory Title Date of Accession Full ID Author [R] optional Display ID [R] Abstract Subject [R]. Comment [R] Date for Discovery [R] Dublin Core-ish Minimal Metadata for selective harvesting
Implementation efforts Implementation of Dienst subset –arXiv.org done –Cornell NCSTRL server done –WCR done –RePEc fails Harvesting arXiv NCSTRL for a test library
Critique Why OAMS, not Dublin Core Dienst subset carries a lot of legacy to the full dienst protocol that.
development in DL community Interest in interoperability for a long time, stated interest of the digital library federation trouble: two approaches –union catalogue causes friction –distributed search high entry requirement problematic to implement
Harvard meeting 2000-05 Vision statement: SFc a new way forward for interoperability could the OAi develop in a more general fashion such that it can be used by different communities? political agenda of OAi (free access) perceived as problem
San Antonio meeting 2000-06 45 people show broad range of interest leads to problem of not getting lost. View that SFc is a technical support infrastructure Communities in different business and contents model can adopt the framework for interoperabilty
San Antonio meeting 2000-05 Carls reverse bubble –First there was the OAi that made the SFc. –Now there is the SFc that is implemented by more than the original OAi discussion of what changes required to the OAi –steering committee –attract funding to develop other application domain
Ithaca meeting 2000-09 Experience gained with implementing & discussing the current SFc specs aim: new spec by the end of 2000 stable for experimentation but not definite hope to minimise risks for implementors maximise chances for interoperability SFc+ to translate from eprint domain interoperability towards general domain interoperability
Abstract concepts to keep open eprint archive --> open archive data provider / service provider archive management issue of records needed to be discussed OAMS confuses metadata and full text
Implementation features to keep Metadata harvesting OAi namespace shared metadata and parallel metadata acceptable use registration of data and service providers
All change please, all change... OAi DIENST replaced by OA protocol OAi ID revised OAMS replaced by wrapped DC introduction of the concept of native metadata generalised and marginalised partitions revisited registrations
New OAi metadata Accession date to be renamed datestamp and stripped of semantic link to the records Full ID kept, colon used as canonical separator unqualified DC is mandatory, but empty DC may be returned introduction of the idea of native metadata OAMS scrapped, Krichel and Warner to lead an EPMS discussion
Solution: encapsulate metadata dini:01 2000-09-21 Someones paper
Identifier Identifiers point to metadata records Concatenate –Case sensitive archive name –delimiter is a colon –anything internal to the archive appearing after that prefixed by OAI as a pointer to a resolution mechanism
Sets replace partitions ONLY for a local community to implement selective harvesting there can be zero or more sets in an archive records can exist at interior nodes in the set hierarchy asking for records in a set returns records in the set and in all its subsets.
OA protocol Identify (no arguments, no exceptions) ListMetadataFormats ([fullId]), response is the same as for the SFc ListSets (no arguments, empty response ok) ListRecord ([Sets] colon as separator)
OA protocol ListContents ([sets][recordbefore] [recordafter][metaformat]) –response as before but may contain –resumption token (set,recordbefore,recordafter) –errors 206,503,302 GetRecord (fullId) –response as before –error 404
Encoding via cgi General syntax baseurl?verb=verbname&argname=argval... baseurl is the location of the OA v1 protocol as registered at openarchives.org verbname is the name of the verb argname is the name of the attribute argval is the value of the attribute
Registration of archives Metadata format registration as now, names alphanumeric and underscore Self-description introduced in the OA protocol through the identify verb Fields of data provider templates –Natural language name –description url –archive id –maintainer (of OA interface) email –version of OA protocol used –OA base url
Conclusion After the Ithaca work, the OAi is set for another time of testing, with a broader set of tests rather than at the first time. Many ideosyncracies of the old SFc have been removed, and that will increase the overall acceptability. The new version one of the OAi protocol may be a bit more complicated than the SFc, but a lot more sound. It still is not definite.