- From: Adrian Heilbut <adrian.heilbut@utoronto.ca>
- Date: Fri, 27 Aug 1999 19:12:13 -0400
- To: www-annotation@w3.org
I've also been lurking for a bit, and thinking quite a lot about annotations. Another possible starting point for prototyping is a product called Muffin (http://muffin.doit.org), which is a GPLed, HTTP proxy in Java with very nice interfaces for what it calls "filters," which allow one to modify documents before sending them to the browser. It actually already contains a very rudimentary glossary filter, although one that only works with a local glossary file. On proxies vs. mediators: (partly to see if my understanding is correct...) A mediator is a more abstract concept than a proxy. A proxy is an implementation mechanism for a mediator. A proxy is any software that supports the http proxy protocols. The reason that the term "local proxy" makes sense is that "proxy" is a well understood and universally supported mechanism for piping http requests through an extra level of sofware. Local just means that it runs on the same machine as a browser. If an annotation system is going look like a proxy as far as the browser is concerned, it remains a proxy, even if it mediates by modifying the data passing through. Muffin, by this definition, is a local proxy. Thirdvoice is not. Both, however, are local mediators. Crit, a mediator, is not a proxy, but it could be modified to be a "mediating remote proxy", which would eliminate the funny URLs. There is not going to be a single optimal implementation. A remote mediator might well be the optimal solution to annotating pages on a handheld device, for example. Proxy implementations suffer from the limitations of a web interface, so the slickest software might well be a "client helper" like Thirdvoice, or code integrated in Mozilla. As Jon pointed out, the most important thing is to come up with a consistent ontology for annotations, and then to specify annotation documents, ideally in XML, that would be transported through HTTP. It should be possible for the description of an annotation to be completely independent of its implementation. The mediator would be responsible for finding annotations, through indexes, subscriptions, or whatever. (I like the idea of web pages suggesting annotation channels.) I'm going try to start hacking something together with Muffin, starting off with a first shot at a very simple XML annotation spec. I'm also be interested in the workshop. Cheers, Adrian -- adrian.heilbut@utoronto.ca http://www.syncytium.net tel: 416-781-5341 ICQ: 8932453
Received on Friday, 27 August 1999 19:11:01 UTC