amir@smsc.sony.com (Amir ) (03/07/90)
In article <00933399.8ACEFBE0@KING.ENG.UMD.EDU> sysmgr@KING.ENG.UMD.EDU (Doug Mohney) writes: >The Japanese and Taiwanese and the Koreans (South, of course) all have >plans to go do SPARC implementations; look for Toshiba to give us portable >SPARC, Taiwan and Korea to give us $5K SPARC boxes which will compete with >Sun and DECs low-end machines. This brings up another topic. Toshiba, as the poster mentioned, has long been rumored to be making a "portable" SPARC systesm. Can anyone speculate as to how successful a *portable* Unix box would be specially when the competition is 286/386 machines that run both DOS and Unix applications? Off course, SPARC machine would run faster but what kind of people would need the extra speed? Note that I am not saying that this is not a good idea. It is just that what most people do with a portable machine can be done with current intel based portables... -- Amir H. Majidimehr Operating Systems Group Sony Microsystems amir@smsc.sony.com | ...!{uunet,mips}!sonyusa!amir
sysmgr@KING.ENG.UMD.EDU (Doug Mohney) (03/07/90)
In article <1990Mar6.184634.14749@smsc.sony.com>, amir@smsc.sony.com (Amir ) writes: >This brings up another topic. Toshiba, as the poster mentioned, has long been >rumored to be making a "portable" SPARC systesm. Can anyone speculate >as to how successful a *portable* Unix box would be specially when >the competition is 286/386 machines that run both DOS and Unix >applications? Off course, SPARC machine would run faster but what >kind of people would need the extra speed? > The military might not mind having a few which run like lightening. With the government push towards POSIX, portable UN*X boxes will eventually, someday, find a niche. >Note that I am not saying that this is not a good idea. It is just that >what most people do with a portable machine can be done with current >intel based portables... Weeel, how good is a UNIX box without a network to connect it to? This might be the limiting factor in running portable UNIX since (in my finite wisdom) UNIX boxes are either used for multiuser things, network things, or workstation things which usually want 1024 x 768 or something equally pretty which you won't find out of current LCD technology.
sauer@dell.dell.com (Charlie Sauer) (03/07/90)
In article <00933484.3084BF80@KING.ENG.UMD.EDU> sysmgr@KING.ENG.UMD.EDU (Doug Mohney) writes: >Weeel, how good is a UNIX box without a network to connect it to? This Some laptops, e.g., Dell 316LT, are capable of running Unix (in this case on 386SX) and are capable of being connected to LAN's/WAN's. 316LT has one slot for standard PC half-length cards, e.g., Ethernet, 3270, ... -- Charlie Sauer Dell Computer Corp. !'s:uunet!dell!sauer 9505 Arboretum Blvd @'s:sauer@dell.com Austin, TX 78759-7299 (512) 343-3310
henry@utzoo.uucp (Henry Spencer) (03/16/90)
In article <1177@kunivv1.sci.kun.nl> ge@kunivv1.sci.kun.nl (Ge' Weijers) writes: >... There is a limit, of course, but by using a 100Mhz wide band >and decent modulation techniques quite a lot of 64Kbit connections can >be managed. I'm not an expert on this by any means, but the EEC ... >... have planned precisely such a network for the middle 90s, and >I suspect the plan is perfectly feasible :-) That plan probably is feasible; the trouble is that 64Kb/s is far below the sort of speed many people would like to see. Try fitting 10Mb/s channels, or even 1Mb/s channels, in and it's not so easy any more. Phone companies, accustomed to thinking in terms of modems, seem to feel that 64Kb/s is an enormous data rate, as witness glowing predictions of the wonders of ISDN. And it actually is quite a respectable data rate if you're thinking in terms of electronic mail, maybe a bit of Usenet news :-), telnet, and the like. For distributed applications, it's nothing at all. And yes, people will want do such things from their laptops. -- MSDOS, abbrev: Maybe SomeDay | Henry Spencer at U of Toronto Zoology an Operating System. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
bzs@world.std.com (Barry Shein) (03/17/90)
>p.s. The relevance of any of this to comp.arch is that no matter how the >parts of our chips or systems talk to each other, the channels are of >finite bandwidth. And no matter how we encode the data in our registers, >there will be noise introduced in moving that data. So at some level the >Nyquist & Shannon limits put a cap on (sequential) computation speed. > > >----- >Rob Warnock, MS-9U/510 rpw3@sgi.com rpw3@pei.com Thanks for a good explanation Rob. I got all sorts of responses to this, most trying to point out the Shannon Limit, some snidely, yes all, I was aware of it, that's what I was referring to, people used the Shannon limit to "prove" to me and others that you couldn't get much more than 3Kb/s out of a voice-grade phone line. But my point lies in your last phrase, and you're reference to things like QPSK etc. Just that it's a bit facile for someone to say "it's impossible to get sufficient bandwidth out of a radio signal to make it interesting for networking (no, not begging the question of "interesting".) If I can send 10Kb/s on an RF channel, and I can get 1536 or so channels to use then I can send (roughly, yeah yeah, preambles etc) 10K ethernet-equivalent packets per second, about 50% faster than the theoretical limit of an ethernet which I'd call "interesting". All I need is the ability to mux/demux 1536 RF channels (I believe the speed is quite swallowable), is that utterly unfeasible? I don't think so, might take some creativity with the spectrum to let a lot of people do that. Isn't this the kind of thing the C3I spooks do all the time? Maybe we can't talk about this. The obvious thing is to use a few dozen more channels and do ethernet style addressing in the chips and mux many people onto the same channel band. Then the FCC probably only has to approve a few ranges or some such thing per metropolitan area. Eavesdropping of course begs for encryption, so don't start that. Anyhow, never say never. I guess. -- -Barry Shein Software Tool & Die | {xylogics,uunet}!world!bzs | bzs@world.std.com Purveyors to the Trade | Voice: 617-739-0202 | Login: 617-739-WRLD