Date: Tue, 30 Jun 92 11:57:55 +0200 From: jfg@dxcern.cern.ch (Jean Francois Groff) Message-Id: <9206300957.AA19493@dxcern.cern.ch> To: davis@willow.tc.cornell.edu (Jim Davis) Cc: www-talk@nxoc01.cern.ch Subject: Re: Raisch's Attention link > As for charging, fairness requires that the link not be activated > until I have seen a warning (otherwise I might get charged a zillion > dollars to read the document - just like 900 phone numbers in the > USA). So this will add complexity to the client. This is of course very important! But just adding an alert in the client before spending money is not a complex change. It might just be annoying to the user (had you rather be annoyed or spend $$$ ?) The user could also want to authorize access without warning to trusted data sources, e.g. a pay-by-time database that he uses frequently (with the stress of the ticking $ clock in the corner...) > Also, attention links are not sufficient for a charging. They > support a model where I am charged once per read, no matter how much > of the document I read. But it seems likely that there might be need > for other charging models. For a discussion of the many problems of a read-based charging scheme (which was to be implemented in Xanadu as an answer to the Copyright issues), you may want to read a paper presented at the Hypertext'91 conference in San Antonio, by Pamela Samuelson and Robert Glushko, "Intellectual Property Rights for Digital Library and Hypertext Publishing Systems: an Analysis of Xanadu" (unfortunately not available online to my knowledge...) -- Jean-Francois Groff (jfg@info.cern.ch) World-Wide Web initiative CERN, ECP division, CH-1211 Geneva 23, Switzerland Phone +41 22 767 3755 -- Fax +41 22 767 7155 -- "Life may at times be boring, but is it more fun to be dead ?" -- Alcor