At 10:51 AM 04/11/2002 -0700, Tim May wrote: >No, we have AC because AC works better than DC in home wiring situations.
Most of the telco business runs on 48V DC, and much of the "off-the-grid" solar energy electric applications run fine on 12V DC. The big advantages of AC are for motors. >And the issue of patents on software is a _metering_ problem. Software patents have major problems with interfering with authors by forcing them to identify relevant patents. Even if the patent office actually had examiners skilled in the field who had real understanding of prior art and didn't approve bogus patents right and left, it's still impractical for the average software author to wade through 5 million patents before writing a product, especially since patents are deliberately written in patentese, to maximize the potential scope of their claims while minimizing the amount of actual information revealed in the patent. You can't spend years of work just trying to tell if your latest variation on an XOR cursor has already been patented, especially if you're an amateur rather than a business. There are obviously patents that are well-known, well-publicized, and relatively clear in what they're covering, like RSA and Diffie-Hellman, and the "metering problem" of how to pay for licensing was quite serious for some of them (even for patents whose owners didn't threaten to run you over in the parking lot :-) and no problem for others (Tim's examples with microprocessors.) But it's the patents that you didn't know when writing your application about that can really cause you trouble - some things like RSA are novel and hard to discover, so if you're using them, you heard about them from the patent-holders, but some like "automatically encrypt a filesystem" are likely to be reinvented, and if you put your product out in the field and *then* find that somebody else has a patent on it (or was in the process of applying for the patent when you were doing your development) then they've got you by the kneecaps. In theory you can contest a patent that was awarded for something that would be obvious to a skilled practitioner, in addition to contesting patents on things that were prior art, but a serious product may have dozens of critical features any one of which could kill you, and if any of them was for something that's obvious enough that you discovered it independently, you're in trouble. In the current system, of course, it's much worse, because the incompetence of the patent office means that they can't tell something that's obvious to a skilled practitioner from something that's obvious to an unskilled practitioner or only obvious to a few experts, and their willingness to accept "business method" patents means that there are all sorts of bogus patents on things like "make money by putting catalogs on line and accepting credit cards" or "do common-practice-X using *the Internet*" as well as bogus patents on actual technology.
