Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!ucsd!ucbvax!ANDREW.CMU.EDU!ms6b+ From: ms6b+@ANDREW.CMU.EDU (Marvin Sirbu) Newsgroups: comp.mail.multi-media Subject: Re: the debate between Jon and Craig Message-ID: Date: 24 Aug 90 02:38:19 GMT Sender: daemon@ucbvax.BERKELEY.EDU Distribution: inet Organization: The Internet Lines: 70 Jonathon's original list of possible starting points for document standards included CDA from DEC. In fact, DEC provides for exactly the notion that Craig describes of sending along application code, or the name of the appropriate application to use, in order to view/edit/manipulate a particular type. Because CDA was designed by DEC to support the DEC product family, (only two hardware architectures) DEC can assume that the requisite applications are available throughout the universe DEC intended CDA to operate in. The idea of using some widely available program and its data file as a component of multimedia mail has several defects: 1) you are limited to the capabilities of the particular software package in terms of that type. If Lotus 1.0 is your standard for spreadsheets, they you can't send three dimensional spreadsheets. Jon made a similar point using the example of margins. 2) you are limited to the platforms which support the standard application. or at least support the standard application's file format. (I can send a Lotus file to a Mac and read it with Excel because the Lotus file format is widely read.) It also has some advantages. Now, the fact is that IBM PCs are so widespread that a lot of useful multimedia interchange could conceivably take place just by sending around combinations of Word Perfect + Lotus files. And those who are anxious to get some real multimedia going now, but don't care about universality and generality can get started that way. By contrast, if you believe that 1) we need standards that support interchange with machines that Lotus doesn't run on (yet...); or 2) if we look at the functionality of lots of spreadsheet programs (substitute text, graphics, music, etc.) we can define a file format which supports the union of all the capabilities in all of them, then, you try and develop or extend something like ODA. Standards like the ISO standard for exchanging computer tape at 800 bits per inch started out as the IBM tape drive product. Because IBM tape drives were out there, there were a lot of them, and they worked, other vendors made products that would work with the IBM written tapes. Eventually, the characteristics of the IBM product were written down as a standard. The de facto capabilities of the IBM product, and its limitations, became the stanadard because that was the easiest thing to do. The test for compatibility was, "Can a tape written on drive X be read by an IBM drive?" By contrast, other standards, like the Intelligent Peripheral Interface (IPI) represent technological combinations which were put together for the first time in a committee, and attempted to include ideas from many different sources. There was no reference implementation, and each vendor worked on implementations which would conform to the document, not to some reference implementation. Not every implementation of IPI provides all the features of the documented standard. So both approaches to standards development have historical precedent. However, it is worth pointing out that there has been a relative decline in the success rate of de facto standards, and a marked increase in standards designed by committees over the last 15 years. While I am not sure I can explain why fully, I believe it is because of the increasing heterogeneity of information technology hardware and users. There are no firms with the dominating power of an IBM or AT&T of the 1960s, nor, arguably, is even the IBM PC such a dominant de facto architecture. Thus, it is not realistic to expect a standard developed around "popular" applications to become a sufficient de facto standard to really be universal. On the other hand, standards processes are so slow, that you can do an awful lot of useful work based on the other approach while standards are being developed -- as, evidently, DEC has decided in bringing out CDA. Marvin Sirbu CMU