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DOS 6.0 and Compression?

John Bittner writes:

I just saw a demo of DOS 6.0 at the Infomart in Dallas Texas. It has many new features such as built-in backup software, undelete, move, transparent hard disk compression, hard disk defragmentation, memory management improvement, and built-in anti-virus software.

The file compression will work with floppy disks which should double their capacities. I asked the rep if Apple File Exchange would be able to read a compressed floppy. He did not know. I doubt it will. DOS 5.0 will not be able to read compressed floppies either. Will they have to rewrite Apple File Exchange (AFE) to read them? Will Mac users need a new floppy drive to use AFE on the compressed floppies?

[We don't expect Macintosh users will need new floppy drives to read compressed disks, but we doubt that AFE will function correctly with DOS 6.0 compressed disks. Apple may not update AFE but might instead update the commercial Macintosh PC Exchange to handle those compressed disks. Third-parties such as DataViz will probably sell solutions relatively quickly. -Adam & Tonya]

Information from:
John Bittner --

Microsoft and Stac -- Stac Electronics, compression software leader in the PC world and soon to be a compression contender in the Mac arena with its driver-level compression utility Stacker, claims that the compression capabilities in DOS 6.0, called DoubleSpace, infringe on two of Stac's compression patents. Here's an abbreviated version of the story from Stac's lawsuit.

As Stacker for DOS became popular, Mr. Bill became interested in the technology and asked the president of Stac to contact Microsoft about including it in DOS. Keep in mind that DOS's main competitor, DR-DOS from Novell, already includes compression capabilities. Stac and Microsoft negotiated licensing issues, and Microsoft refused to pay any royalty to Stac for the license, making it clear that if they didn't use Stac's technology, they would use someone else's, and even at one point showing Stac a spreadsheet outlining the adverse impact on Stacker's sales if this happened. As negotiations continued, it became clear that Microsoft wanted Stac's technology but didn't want to pay for it. Irritated, Stac broke off the talks. Finally, Microsoft called Stac again, because they determined that their own compression code infringed on at least one of Stac's patents. Microsoft promised to send Stac a licensing proposal and a beta of DOS 6.0. A month or so later, in January of 1993, Microsoft sent the beta, but included a note saying essentially "Don't worry about the patent stuff. We are just going to keep our changed code which does not infringe."

All fine and nice, but when Stac examined the beta, they determined that it infringed on two of Stac's patents. That's not the end of the story though. Microsoft sent Stac a preliminary press release that Microsoft plans to license, for free, the compression code in DoubleSpace, to all comers to create an opportunity for third parties to enhance DOS 6.0's compression features with add-on boards, chips, and software. Needless to say, Stac was not pleased, and brought in the legal howitzers.

Interestingly, although Stac seems like the poor, downtrodden underdog in this case, their white hat is a bit soiled. Remember the DoubleUp compression board from Sigma Designs that used Salient's DiskDoubler as an interface? Well, that board used a chip from Stac, and after Stac received a patent on their algorithms, licensing talks with Salient bogged down even though Salient only needed to license the expansion code since the Stac chip on the DoubleUp board handled compression. Although no one specifically identified any malice on Stac's part, we do wonder if Stac's forthcoming Stacker for Macintosh might have played a role in the talks falling apart.

It's a nasty world out there - I'm amazed at how pleasant most people on the Internet are in comparison to what goes on in real life.


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