- From: Mike Taylor <mike@tecc.co.uk>
- Date: Thu, 27 Sep 2001 11:31:20 +0100
- To: www-zig@w3.org
Dear ZIGgers, In the light of the current pre-ZIG discussions of ZNG, I would like to draw people's attention to a complementary approach to some of the problems that ZNG addresses. To recap, those problems include, but may not be limited to, the following: New Z39.50 programmers find it hard to assimilate the big, scary standard document. Building Z39.50 applications takes too long because it's generally necessary to write low-level networking code. Programmers find it difficult to write ASN.1/BER code. The ASN.1/BER substrate is seen as old-fashioned. While ZNG's approach to these problems is to change the implementation of the protocol, ZOOM adopts the alternative approach of hiding the complexity behind a simpler, application-level, interface -- so that applications need not know about the gritty low-level details any more than SOAP applications need to know about the details of XML syntax and HTTP transport. ZOOM stands for The Z39.50 Object-Orientation Model. It presents a useful subset of the Z39.50 services in terms of an abstract OO API. In order to ground this initiative in reality and make it work for real people building real applications, it needs concrete bindings to real languages. We currently have three such bindings on the table: a Perl binding, which is fully implemented and documented, and in use in commercial projects; a C++ binding, which is designed and in the process of implementation; and a C binding, which is at the design stage. We plan to present the current version of the ZOOM specification at the Boston Spa ZIG; I'll also distribute copies of the document (about three and a half thousand words, or eleven nice, easy-to-read pages). In the ensuing discussion, I hope that we can get some useful feedback on issues including the following: How well does the API walk the line between simplicity and power? For example, should it support encapsulation, including or limited to the special case of "piggy-backed" searches? To what extent should the presentation of the ZOOM specification attempt to "hide" more advanced features (such as sort, scan, asynchronous operation) so that the core simplicity shines through? How many separate documents should there be? For which languages, other than Perl, C++ and C, would it be useful to have a ZOOM binding? (In other words, what languages do people want to use for building Z39.50 apps?) How can we achieve a competitive diversity of implementations? In the current version of the agenda at http://lcweb.loc.gov/z3950/agency/zig/meetings/uk2001/agenda.html Ray has the ZOOM presentation and discussion down as on of the "Briefings". However, since ZOOM attempts to address some of the same concerns as ZNG, I wonder whether it might be better to discuss ZOOM as a part of, or immediately after, the ZNG sessions? I can supply a URL to the current, work-in-progress version of the ZOOM specification to anyone who is particularly interested. Email me on <mike@tecc.co.uk> if you'd like to see it before the ZIG. Thanks for listening. _/|_ _______________________________________________________________ /o ) \/ Mike Taylor <mike@miketaylor.org.uk> www.miketaylor.org.uk )_v__/\ "The cladistic defintion of Aves is: an unimportant offshoot of the much cooler dinosaur family which somehow managed to survive the K/T boundry intact" -- Eric Lurio.
Received on Thursday, 27 September 2001 06:31:28 UTC