amc4919@cec2.wustl.edu (Adam M. Costello) (05/06/91)
Would anyone care to speculate how long it will be before we see modems with 19200 bps physical data rates? I assume it's being worked on. Are there any rumors floating around? AMC
dave@cs.arizona.edu (Dave Schaumann) (05/06/91)
In article <1991May5.201708.452@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >Would anyone care to speculate how long it will be before we see modems with >19200 bps physical data rates? I assume it's being worked on. Are there any >rumors floating around? >AMC There are already 38K baud connections (direct connect). I believe that a normal phone line is physically incapable of carrying more than a few thousand baud at best, due to bandwidth limitations. Perhaps when optical connections become commonplace, the phone companies will be able to afford to consider restructuring the phone transmission protocols, perhaps selling wider-band width lines at a premium rate. But until the phone companies see this as a paying proposition, I doubt it will happen. -- Dave Schaumann | There is no cause so right that one cannot find a fool dave@cs.arizona.edu | following it. - Niven's Law # 16
rodent@netcom.COM (Ben Discoe) (05/06/91)
The key phrase here is "When will ISDN be easily available?" I wish there were more people hollering for it; I can't wait. I refuse to buy a grossly expensive 9600 baud modem to run on a lowly, pathetic VOICE LINE. Everybody say "I want my ISDN!" ------------- Ben Discoe, radical ecologist, computer scientist, visionary at large.
muzzle@cs.uq.oz.au (Murray Chapman) (05/06/91)
Hang on! Doesn't the TrailBlazer modem do 19200 baud???? (The TrailBlazer sends data in parllel down a 'phone line by using different frequencies... automatically mapping out bad bands. I have also heard a rumour that a TrailBlazer GUARANTEES 100% data transmission, even to the point of faking "OK" messages. One catch: you need a TrailBlazer at each end of the connection. :-) )) I have heard of a case where the radio link to an oil rig was down, and the only phone line out to the rig had so much static that voice communication was impossible... but the TrailBlazer made it through! (Selecting "good" frequency bands). +^o^+^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-+-o-+ | | Murray Chapman muzzle@cs.uq.oz.au | | | o | | o | | | University of Queensland "I'd rather have a bottle in front | | | o | St Lucia, Queenland of me than a frontal lobotomy" | o | | | AUSTRALIA - Mel Brooks | | | o | | o | +^-^+^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-^-------------+---+ \__ | o | Hate that! -----> +^-^-^-^-^-^-^-
cactus@zardoz.club.cc.cmu.edu (Todd Masco) (05/06/91)
In article <1492@caslon.cs.arizona.edu> dave@cs.arizona.edu (Dave Schaumann) writes: > I believe that a normal phone line is physically incapable of > carrying more than a few thousand baud at best, due to bandwidth > limitations. False, unless "more than a few" is over 19.2. At Carnegie Mellon, we have an experimental service called MCN ("Metropolitan Campus Network") that gives us a indirect DOV ("Data Over Voice") connection to campus. This connection, at 19.2 KBaud, is running over two of the four wires in the line going out of our house. The other two, of course, make our voice line. It's all controlled through a computer owned by TPC ("The Phone Company"). (We currently run SLIP between a Sun 3 and a VAX running Multinet on campus. It works quite well, putting our house thin ethernet (used to be thick -- long story) on the Internet. Which brings me to *my* question: What's the cheapest *reasonable* Ethernet hardware/software combination available for the Amiga? I'll be "Powering Up" to an A3000 in the very near future, and would really like to put it on our net. However, I don't quite feel like shelling out $500 for it. From what I know about KA9Q, I'm hesitant to go with it. On the other hand, if using it and an under $200 Ethernet card (am I dreaming?) is the alternative to the Commodoe $500 deal... [Sheesh. With a UNIX Amiga, I'd expect Ethernet to come way down. Hasn't from what I've seen...] -- Todd L. Masco - CMU Physics | "Free speech is the right to shout "theatre" cactus@zardoz.club.cc.cmu.edu | in a crowded fire."
dillon@overload.Berkeley.CA.US (Matthew Dillon) (05/07/91)
In article <1991May5.201708.452@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >Would anyone care to speculate how long it will be before we see modems with >19200 bps physical data rates? I assume it's being worked on. Are there any >rumors floating around? >AMC A normal phone line has a bandwidth of around 38KBaud. As any RF/electrical engineer will tell you, it's nearly impossible to utilize all the available bandwidth of a medium. It's hard enough to utilize half of it, which is what 9600bps (V.32) modems do now (9600bps full duplex = 19.2KB bandwidth). The best you will ever see on a phone line is probably around 19.2KB uncompressed. Now, on leased lines or dedicated direct connects you can get a hellofalot better throughput. -Matt -- Matthew Dillon dillon@Overload.Berkeley.CA.US 891 Regal Rd. uunet.uu.net!overload!dillon Berkeley, Ca. 94708 USA
allbery@NCoast.ORG (Brandon S. Allbery KB8JRR/AA) (05/07/91)
As quoted from <1187@uqcspe.cs.uq.oz.au> by muzzle@cs.uq.oz.au (Murray Chapman): +--------------- | Hang on! Doesn't the TrailBlazer modem do 19200 baud???? +--------------- The Trailblazer gets 18400 baud using compression; the maximum uncompressed rate is 10600 baud. Unidirectional; it has to turn the line around to send data the other way, which is why the TB has the various "spoofing" modes in it. +--------------- | heard a rumour that a TrailBlazer GUARANTEES 100% data transmission, even | to the point of faking "OK" messages. One catch: you need a TrailBlazer at | each end of the connection. :-) )) +--------------- Depends on what you mean by "faking 'OK' messages". Telebit spoofing works as follows: the modem does the protocol (X/Ymodem, Kermit, or UUCP) to the local computer, but does its own protocol between the modems. So it "fakes" ACK packets, but the data *does* go through --- not even call waiting fazes the Telebit protocol. +--------------- | I have heard of a case where the radio link to an oil rig was down, and the | only phone line out to the rig had so much static that voice communication | was impossible... but the TrailBlazer made it through! (Selecting "good" | frequency bands). +--------------- True. The TB may degrade its speed, but it does so in *small* pieces; it can drop single carrier frequencies instead of dropping the whole line speed. I am given to understand that on lines that are so dirty that voice is impossible, the TB can still do AT LEAST 4800 baud --- if the noise is confined to certain frequency bands, it can do the full 10800 baud. ++Brandon -- Me: Brandon S. Allbery Ham: KB8JRR/AA 10m,6m,2m,220,440,1.2 Internet: allbery@NCoast.ORG (restricted HF at present) Delphi: ALLBERY AMPR: kb8jrr.AmPR.ORG [44.70.4.88] uunet!usenet.ins.cwru.edu!ncoast!allbery KB8JRR @ WA8BXN.OH
lshaw@ccwf.cc.utexas.edu (logan shaw) (05/07/91)
In article <1492@caslon.cs.arizona.edu> dave@cs.arizona.edu (Dave Schaumann) writes: >There are already 38K baud connections (direct connect). I believe that a >normal phone line is physically incapable of carrying more than a few thousand >baud at best, due to bandwidth limitations. Perhaps when optical connections >become commonplace, the phone companies will be able to afford to consider >restructuring the phone transmission protocols, perhaps selling wider-band >width lines at a premium rate. I believe Northern Telecom phone switches already support digital modems. (Northern Telecom supplies telecommunications hardware to both MCI and US Sprint). In the long-distance telecommuncations industry, most everything is already all-digital. The problem is essentially the local service and the wire in your house. >But until the phone companies see this as a paying proposition, I doubt >it will happen. Ah, they do, especially if one phone company has it and another doesn't. The problem is that it's an *extremely* expensive proposition that involves replacing all the wires that the phone network consists of with fiber. That takes a _long_ time, and _alot_ of money. -Logan -- // # "He said that He had your number; you cut the telephone line. \X/ # You said you needed a reason; He said 'there ain't much time.' Logan # You kept trying to avoid it; He kept knocking on the door. Shaw # In a flash it was over; you were a prisoner of war." -Rez Band
amc4919@cec2.wustl.edu (Adam M. Costello) (05/07/91)
In article <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: > half of it, which is what 9600bps (V.32) modems do now (9600bps full > duplex = 19.2KB bandwidth). The best you will ever see on a phone line You say that current 9600bps modems can sustain that rate in both directions? Then it should be no problem to have 19200bps one direction (and, say, 1200bps the other). I think this would be far more useful anyway. In my experience, the traffic is always much greater in one direction. AMC
jay@deepthot.cary.nc.us (Jay Denebeim) (05/07/91)
In article <1492@caslon.cs.arizona.edu> dave@cs.arizona.edu (Dave Schaumann) writes: >>In article <1991May5.201708.452@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >> >>There are already 38K baud connections (direct connect). I believe that a >>normal phone line is physically incapable of carrying more than a few thousand >>baud at best, due to bandwidth limitations. Perhaps Phone lines have a 4Khz analog bandwidth. Direct digital (ISDN) gives you 64KBaud. These are the absolute maximums. >> >>-- >>Dave Schaumann | There is no cause so right that one cannot find a fool >>dave@cs.arizona.edu | following it. - Niven's Law # 16 -- |_o_o|\\ |. o.| || The Jay Denebeim | . | || Software | o | || Distillery | |// Address: UUCP: mcnc.org!deepthot.uucp!jay ====== Internet: jay@deepthot.cary.nc.us BBS:(919)-460-7430 VOICE:(919)-460-6934
dale@boing.UUCP (Dale Luck) (05/08/91)
In article <12927@pt.cs.cmu.edu> cactus@zardoz.club.cc.cmu.edu (Todd Masco) writes: > >What's the cheapest *reasonable* Ethernet hardware/software > combination available for the Amiga? I'll be "Powering Up" to an > A3000 in the very near future, and would really like to put it on our > net. However, I don't quite feel like shelling out $500 for it. Well, if by your message you are a student at a University then you do not need to shell out $500. The educational price we have for the A2065(ethernet) + AS225(tcp/ip) is $428.00 >From what I know about KA9Q, I'm hesitant to go with it. On the other > hand, if using it and an under $200 Ethernet card (am I dreaming?) is > the alternative to the Commodoe $500 deal... Well the A2065 is not quite under $200; it is only a tad more though. How about $229 for students at Universities. The A2065 board is a full 16bit board with 32kbytes of on board RAM for packet cache. It is fully autoconfig compatible and supports thin and thick net. >[Sheesh. With a UNIX Amiga, I'd expect Ethernet to come way down. > Hasn't from what I've seen...] But it has! This same setup 2 years ago cost $900 for hardware and tcp/ip software. For students it is half the price it used to be! >Todd L. Masco - CMU Physics | "Free speech is the right to shout "theatre" >cactus@zardoz.club.cc.cmu.edu | in a crowded fire." Dale Luck GfxBase, Inc. 1881 Ellwell Dr. Milpitas, Ca 95035 408-262-1469 fax=408 262 8276 Disclaimer: GfxBase markets, sells, and supports the A2065 and the AS225 products mentioned above. For more information please contact us. -- Dale Luck GfxBase/Boing, Inc. {uunet!cbmvax|pyramid}!amiga!boing!dale
drysdale@cbmvax.commodore.com (Scott Drysdale) (05/08/91)
In article <48579@ut-emx.uucp> lshaw@ccwf.cc.utexas.edu (logan shaw) writes: >In article <1492@caslon.cs.arizona.edu> dave@cs.arizona.edu (Dave Schaumann) writes: >>There are already 38K baud connections (direct connect). I believe that a >>normal phone line is physically incapable of carrying more than a few thousand >>baud at best, due to bandwidth limitations. Perhaps when optical connections >>become commonplace, the phone companies will be able to afford to consider >>restructuring the phone transmission protocols, perhaps selling wider-band >>width lines at a premium rate. > >I believe Northern Telecom phone switches already support digital >modems. (Northern Telecom supplies telecommunications hardware to >both MCI and US Sprint). In the long-distance telecommuncations >industry, most everything is already all-digital. The problem is >essentially the local service and the wire in your house. > >>But until the phone companies see this as a paying proposition, I doubt >>it will happen. > >Ah, they do, especially if one phone company has it and another doesn't. >The problem is that it's an *extremely* expensive proposition that >involves replacing all the wires that the phone network consists of >with fiber. That takes a _long_ time, and _alot_ of money. that's not really true. ISDN is one local office to customer site digital solution. it works on your existing wiring, and provides two bidirectional 64Kbps channels, and a 2kbps signaling channel. this allows 8khz 8-bit sampled voice on two lines. the big problem ISDN faces presently is the high cost of the customer's equipment. is everyone willing and able to replace all their phones (which cost around $25 nowadays) with $200 phones? ISDN is running in many test installations and lots of corporate locations. many modern pbx'es are actually small ISDN switches. i want ISDN for the 64K "baud" bidirectional serial connection (of course, hooking this up to your serial port is not going to work. you'll need a little box (which perhaps sits on a SCSI bus or a special plug in card)). some of the ISDN phones available have "modems" built in, but they can only talk to other ISDN phones. there are also DSP solutions that are compatible with existing analog modems. but all this costs money, there is no real standard (many companies make ISDN switches, very few can talk to each other), and people aren't exactly clamoring for it. ISDN - I Still Don't Know I Smell Dollars Now Innovations Subscribers Don't Need (my favorite) > -Logan --Scotty -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Scott Drysdale Software Engineer Commodore Amiga Inc. UUCP {allegra|burdvax|rutgers|ihnp4}!cbmvax!drysdale PHONE - yes. "Have you hugged your hog today?" =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
goodwinm@prism.cs.orst.edu (Michael Goodwin) (05/08/91)
In article <1991May7.125031.2331@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >In article <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: >> half of it, which is what 9600bps (V.32) modems do now (9600bps full >> duplex = 19.2KB bandwidth). The best you will ever see on a phone line > >You say that current 9600bps modems can sustain that rate in both directions? >Then it should be no problem to have 19200bps one direction (and, say, 1200bps >the other). I think this would be far more useful anyway. In my experience, >the traffic is always much greater in one direction. This is true. Most telecommunication is done with a person on one side, and how many people type faster than 300 baud? Except for uploads, you should be able to do 19200 remote to local, and about 300 local to remote. Reverse this for file uploads, and this would be almost ideal conditions for modeming. | /\.--.--. /\ | goodwinm@prism.cs.orst.edu | . ) ) ) o / _ / / | Real signatures are in cursive. | ./ / / / .-- /--. .--. (/ \/ | | / / \__/\__/\___/ (__(__(__/\__/\_ |
zerkle@iris.ucdavis.edu (Dan Zerkle) (05/08/91)
In article <1991May6.035952.18592@netcom.COM> rodent@netcom.COM (Ben Discoe) writes: >The key phrase here is "When will ISDN be easily available?" >I wish there were more people hollering for it; I can't wait. I refuse to >buy a grossly expensive 9600 baud modem to run on a lowly, pathetic >VOICE LINE. Everybody say "I want my ISDN!" The city council of Davis, CA has decided that Davis is going to be the first city anywhere to go ISDN. Why? I don't know. I think they are going to link up with the university, which will be nice. A recent newspaper article mentioned the cost of a card for hooking up to the ISDN link -- about the cost of a high-speed modem, not to mention the cost of getting the link installed.... When will this be ready? Probably before I finish my Ph.D. On a side note, the San Francisco talk radio station (KGO 810 AM) had a guest speaker who talked about faxes. He said that the next standard for fax machines will transmit a page in 4 seconds. I called up the show and got him to admit that this would require ISDN optical lines. He also said that CCITT has already approved this standard for the next generation. He also said that there IS in fact a method for error correction in modern faxes, to eliminate the degrading effect of line noise, contrary to what someone here once said. Dan Zerkle zerkle@iris.eecs.ucdavis.edu (916) 754-0240 Amiga... Because life is too short for boring computers.
dltaylor@cns.SanDiego.NCR.COM (Dan Taylor) (05/09/91)
In <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: > A normal phone line has a bandwidth of around 38KBaud. As any There are still a LOT of subscriber lines with 3KHz filters. That is NOT a misprint, 3000 Hz. Some urban subscriber lines have 38KHz, but not many. The higher data rates are achieved by compressing the information in various ways, and using schemes like "trellis coding" to send more "bits per second" than the phone lines can normally stand. Of course, leased point-to-point lines are not normally filtered like this. That's why the older "high-speed" modems worked on them, long before most subscriber lines could. The FAX people have this problem, too. Their machines have many graceful fallback modes. Personally, I WANT an optical ISDN connection as my subscriber line. Dan Taylor
dillon@overload.Berkeley.CA.US (Matthew Dillon) (05/09/91)
In article <1991May7.125031.2331@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >In article <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: >> half of it, which is what 9600bps (V.32) modems do now (9600bps full >> duplex = 19.2KB bandwidth). The best you will ever see on a phone line > >You say that current 9600bps modems can sustain that rate in both directions? >Then it should be no problem to have 19200bps one direction (and, say, 1200bps >the other). I think this would be far more useful anyway. In my experience, >the traffic is always much greater in one direction. >AMC Well, close... if you run half duplex like the HST and Telebit, you still generally need a low-speed return channel to handle ACKs and other incidental data. Why? Because it takes time to 'turn around' the high-speed data direction so if it is possible to return some data without switching you get much better throughput. The split is usually something like 14400/4800 or 18800/400, but you have to be very careful, the equation isn't as simple as choosing a point to split the bandwidth. -Matt -- Matthew Dillon dillon@Overload.Berkeley.CA.US 891 Regal Rd. uunet.uu.net!overload!dillon Berkeley, Ca. 94708 USA
dillon@overload.Berkeley.CA.US (Matthew Dillon) (05/09/91)
In article <1991May07.194745.13866@lynx.CS.ORST.EDU> goodwinm@prism.cs.orst.edu (Michael Goodwin) writes: >This is true. Most telecommunication is done with a person on one side, and >how many people type faster than 300 baud? Except for uploads, you should be ^^^^ ^^^^ >able to do 19200 remote to local, and about 300 local to remote. Reverse this >for file uploads, and this would be almost ideal conditions for modeming. > >| /\.--.--. /\ | goodwinm@prism.cs.orst.edu >| . ) ) ) o / _ / / | Real signatures are in cursive. >| ./ / / / .-- /--. .--. (/ \/ | >| / / \__/\__/\___/ (__(__(__/\__/\_ | > Uh, well .... -Matt -- Matthew Dillon dillon@Overload.Berkeley.CA.US 891 Regal Rd. uunet.uu.net!overload!dillon Berkeley, Ca. 94708 USA
dillon@overload.Berkeley.CA.US (Matthew Dillon) (05/09/91)
In article <1991May6.035952.18592@netcom.COM> rodent@netcom.COM (Ben Discoe) writes: >The key phrase here is "When will ISDN be easily available?" >I wish there were more people hollering for it; I can't wait. I refuse to >buy a grossly expensive 9600 baud modem to run on a lowly, pathetic >VOICE LINE. Everybody say "I want my ISDN!" > >------------- >Ben Discoe, radical ecologist, computer scientist, visionary at large. Well, Motorola's new 68302 microcomputer (a 68HC000 with gobs of IO on-chip) has ISDN capability. It costs around $50 in sample quanities. Add on another $50 in drivers (worst case) and maybe $10 for the board and plastic and I can see an ISDN phone on the order of $110 bucks. (don't forget the x5 industry multiples the cost by :-))... So I would guess an introduction around $300-$500 with the price dropping fast if it catches on. -Matt -- Matthew Dillon dillon@Overload.Berkeley.CA.US 891 Regal Rd. uunet.uu.net!overload!dillon Berkeley, Ca. 94708 USA
iann@cnw01.storesys.coles.oz.au (Ian Nicholls) (05/09/91)
In <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: > A normal phone line has a bandwidth of around 38KBaud. As any > RF/electrical engineer will tell you, it's nearly impossible to utilize > all the available bandwidth of a medium. It's hard enough to utilize > half of it, which is what 9600bps (V.32) modems do now (9600bps full > duplex = 19.2KB bandwidth). The best you will ever see on a phone line > is probably around 19.2KB uncompressed. I thought that the higher speed modems used a different baud from bps. That is, a 2400 bps modem still sends at 1200 baud, it just sends two bits at a time (by phase-shifting; each state uses a different quarter-phase ). The 9600 buad modems use some sort of trellis encoding, so that sixteen states can exist, meaning four bits at a time get sent, but still at 2400 baud (states per second). From this basis, higher speeds can be possible with a more sensitive discriminator circuit, to detect more states. I don't know what the ultimate speed would be, but it won't be cheap. My reference is the Byte magazine, sometime in the past three years. You'll have to look up an index if you want the exact issue. -- "If it's OK to start by stealing pencils, where then do we draw the line?" Ian Nicholls Phone : +61 3 829 6088 Fax: +61 3 829 6886 \_o_/ Coles/Myer Ltd. E-mail: iann@cnw01.storesys.coles.oz.au \\| L1 M11, PO Box 480, Glen Iris 3146, Australia \\
rkent@sparc1.sparc1.csubak.edu (Rick Kent (Student)) (05/09/91)
In article <1991May6.035952.18592@netcom.COM> rodent@netcom.COM (Ben Discoe) writes: >The key phrase here is "When will ISDN be easily available?" >I wish there were more people hollering for it; I can't wait. I refuse to >buy a grossly expensive 9600 baud modem to run on a lowly, pathetic >VOICE LINE. Everybody say "I want my ISDN!" I want my ISDN! I'd love to run a BBS using ISDN. It would be so nice. A link from ISDN into the internet would sure be damn nice too! -- Rick Kent // Only California State University, Bakersfield \X/ Amiga! Internet: rkent@sparc1.csubak.edu AOL: RickK10
drysdale@cbmvax.commodore.com (Scott Drysdale) (05/10/91)
In article <942@cns.SanDiego.NCR.COM> dltaylor@cns.SanDiego.NCR.COM (Dan Taylor) writes: >In <dillon.7375@overload.Berkeley.CA.US> dillon@overload.Berkeley.CA.US (Matthew Dillon) writes: > >> A normal phone line has a bandwidth of around 38KBaud. As any > >There are still a LOT of subscriber lines with 3KHz filters. That is >NOT a misprint, 3000 Hz. Some urban subscriber lines have 38KHz, but >not many. The higher data rates are achieved by compressing the >information in various ways, and using schemes like "trellis coding" to >send more "bits per second" than the phone lines can normally stand. Of >course, leased point-to-point lines are not normally filtered like this. >That's why the older "high-speed" modems worked on them, long before >most subscriber lines could. The FAX people have this problem, too. >Their machines have many graceful fallback modes. > >Personally, I WANT an optical ISDN connection as my subscriber line. optical doesn't buy you diddlysquat for 2B+D service. 2B+D only needs 192Kbits per second, and the encoding and decoding process only requires about 1/3 that frequency to be on the wires between you and the central office. optical connections are useful for multi-megahertz stuff, or very long distances. the wires between you and the phone company (or a termination box) are less than 1 mile long (1/2 mile, i think it is). >Dan Taylor --Scotty -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Scott Drysdale Software Engineer Commodore Amiga Inc. UUCP {allegra|burdvax|rutgers|ihnp4}!cbmvax!drysdale PHONE - yes. "Have you hugged your hog today?" =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
bdb@becker.UUCP (Bruce D. Becker) (05/10/91)
In article <1991May7.001557.23299@NCoast.ORG> allbery@ncoast.ORG (Brandon S. Allbery KB8JRR/AA) writes: |As quoted from <1187@uqcspe.cs.uq.oz.au> by muzzle@cs.uq.oz.au (Murray Chapman): |+--------------- || Hang on! Doesn't the TrailBlazer modem do 19200 baud???? |+--------------- | |The Trailblazer gets 18400 baud using compression; the maximum uncompressed |rate is 10600 baud. Unidirectional; it has to turn the line around to send |data the other way, which is why the TB has the various "spoofing" modes in |it. This isn't quite correct. The Telebit's maximum theoretical speed is 18400 bits per second - but about 20% of that gets eaten up by error correction. This does not have anything to do with compressed data transfers. In fact it is not a good idea to enable data compression for news batches since the modem will attempt to compress data which was already compressed, resulting in a net loss of throughput. In general it is always better to compress data in the machine so that the serial port has as little data to deal with as it can. -- ,u, Bruce Becker Toronto, Ontario a /i/ Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu `\o\-e UUCP: ...!utai!mnetor!becker!bdb _< /_ "It's the death of the net as we know it (and I feel fine)" - R.A.M.
dltaylor@cns.SanDiego.NCR.COM (Dan Taylor) (05/11/91)
In <21448@cbmvax.commodore.com> drysdale@cbmvax.commodore.com (Scott Drysdale) writes: >optical doesn't buy you diddlysquat for 2B+D service. 2B+D only needs 192Kbits I know (thanks for pointing it out, though), but once I have the line, I can run multiple "lines", a WAN, and video through a single connection. The phone companies aren't always the most "public-spirited" of companies, but my service, at least (I know others are different; I've had some of them) has been reliable, and cost-effective. Beats the heck out of the local cable company. I would be willing to buy the higher bandwidth, if the services were available. For one, since I'm a "mail" user, not currently associated with a university, or government lab, I can't get effective "ftp" access to the software repositories on the net. With a WAN, and my "very own" address, I could. I don't know if you've seen it, but the folks at Bell Labs (it's not here, so I can give proper credit) prepared a paper describing a new internal OS, called "Plan 9". They described home access at 1.54 Megabits to office servers. Nice, huh? Dan Taylor
elg@elgamy.RAIDERNET.COM (Eric Lee Green) (05/11/91)
From article <dillon.7457@overload.Berkeley.CA.US>, by dillon@overload.Berkeley.CA.US (Matthew Dillon): > In article <1991May07.194745.13866@lynx.CS.ORST.EDU> goodwinm@prism.cs.orst.edu (Michael Goodwin) writes: >>how many people type faster than 300 baud? > ^^^^ > Uh, well .... > -Matt So we finally know how you can write a "C" compiler in one week's time, eh? :-). Rocket-assisted fingers? -- Eric -- Eric Lee Green (318) 984-1820 P.O. Box 92191 Lafayette, LA 70509 elg@elgamy.RAIDERNET.COM uunet!mjbtn!raider!elgamy!elg
hunter@phoenix.pub.uu.oz.au (James Gardiner [hunter]) (05/11/91)
In <21354@cbmvax.commodore.com> drysdale@cbmvax.commodore.com (Scott Drysdale) writes: >that's not really true. ISDN is one local office to customer site digital >solution. it works on your existing wiring, and provides two bidirectional >64Kbps channels, and a 2kbps signaling channel. this allows 8khz 8-bit >sampled voice on two lines. the big problem ISDN faces presently is the >high cost of the customer's equipment. is everyone willing and able to >replace all their phones (which cost around $25 nowadays) with $200 phones? >ISDN is running in many test installations and lots of corporate locations. >many modern pbx'es are actually small ISDN switches. >i want ISDN for the 64K "baud" bidirectional serial connection (of course, >hooking this up to your serial port is not going to work. you'll need a little >box (which perhaps sits on a SCSI bus or a special plug in card)). some of >the ISDN phones available have "modems" built in, but they can only talk to >other ISDN phones. there are also DSP solutions that are compatible with >existing analog modems. but all this costs money, there is no real standard >(many companies make ISDN switches, very few can talk to each other), and >people aren't exactly clamoring for it. >ISDN - I Still Don't Know > I Smell Dollars Now > Innovations Subscribers Don't Need (my favorite) Here in Australia, ISDN is readily available. Most people do not know this but the AXE exchanges we have all around us now are ISDN machines. At present they are running analog to the normal user but with a flick of the switch and lotsa lotsa lotsa money you get a know phone and ISDN. Thats all that needs to be done... Telecom Australia plan to bring in ISDN as standard. This to a degree is BAD. Telecom have attempted to bring in time local calls for years. This is how they will do it. ISDN is time everything and duoble time on DATA calls. (local calls in Australia are not just in same exchange but in the same City, iner and outer suberbs.) Even though we have ISDN, we may use modems over them as it will probably turn out cheaper then going ISDN data. James.
drysdale@cbmvax.commodore.com (Scott Drysdale) (05/14/91)
In article <1991May11.152050.13051@phoenix.pub.uu.oz.au> hunter@phoenix.pub.uu.oz.au (James Gardiner [hunter]) writes: >In <21354@cbmvax.commodore.com> drysdale@cbmvax.commodore.com (Scott Drysdale) writes: >>ISDN - I Still Don't Know >> I Smell Dollars Now >> Innovations Subscribers Don't Need (my favorite) > >Here in Australia, ISDN is readily available. Most people do not know this >but the AXE exchanges we have all around us now are ISDN machines. >At present they are running analog to the normal user but with a flick >of the switch and lotsa lotsa lotsa money you get a know phone >and ISDN. Thats all that needs to be done... >Telecom Australia plan to bring in ISDN as standard. This to a degree >is BAD. Telecom have attempted to bring in time local calls for years. >This is how they will do it. ISDN is time everything and duoble time >on DATA calls. (local calls in Australia are not just in same exchange >but in the same City, iner and outer suberbs.) >Even though we have ISDN, we may use modems over them as it will >probably turn out cheaper then going ISDN data. it's more or less the same story in most major areas in the US, also. there's ISDN buried in the central office - it's just a matter of hooking the customer's wires to a different line card and flipping some bits in the database. i don't know how the phone system is managed in australia, but around here it's pretty much a free for all as far as which long distance carriers use whose switching equipment. try plugging an AT&T ISDN phone into a northern telecom switch to see how "standard" isdn is. the interoffice stuff has settled down pretty much (though some places are still using SS7 protocol massaging boxes to interface between different "flavors" of SS7). i think by the time ISDN is actually affordable and available to most people, there'll be something even more wonderful right around the corner... >James. --Scotty -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Scott Drysdale Software Engineer Commodore Amiga Inc. UUCP {allegra|burdvax|rutgers|ihnp4}!cbmvax!drysdale PHONE - yes. "Have you hugged your hog today?" =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
elw@netxcom.netx.com (Edwin Wiles) (05/15/91)
In article <1991May7.125031.2331@cec1.wustl.edu> amc4919@cec2.wustl.edu (Adam M. Costello) writes: >You say that current 9600bps modems can sustain that rate in both directions? >Then it should be no problem to have 19200bps one direction (and, say, 1200bps >the other). I think this would be far more useful anyway. In my experience, >the traffic is always much greater in one direction. >AMC Effectively, that's what the French did with their "Datatel" system. (Did I get the name right?) Only they used something like 300 baud from computer to terminal and 30 the other way. That's the jist of it, even if I got the hard numbers wrong. I only remember this from one viewing of a TV show on Discovery. I do remember that they were using some very non-standard [at least in the US] baud rates, with the computer to terminal link being MUCH faster than the terminal to computer link.
kenk@algedi.UUCP (Ken Koster) (05/15/91)
In article <975@boing.UUCP> dale@boing.UUCP (Dale Luck) writes: >In article <12927@pt.cs.cmu.edu> cactus@zardoz.club.cc.cmu.edu (Todd Masco) writes: >> >>What's the cheapest *reasonable* Ethernet hardware/software >> combination available for the Amiga? I'll be "Powering Up" to an >> A3000 in the very near future, and would really like to put it on our >> net. However, I don't quite feel like shelling out $500 for it. >>From what I know about KA9Q, I'm hesitant to go with it. On the other >> hand, if using it and an under $200 Ethernet card (am I dreaming?) is >> the alternative to the Commodoe $500 deal... Sorry, your dreaming :-) :-) The Amiga version of KA9Q does not support any of the available Ethernet cards. Go with the Commodore A2065 and TCP/IP software. -- Ken Koster (N7IPB) algedi!kenk@pilchuck.Data-IO.COM or 14146 73rd PL NE, #201 ...uunet!pilchuck!algedi!kenk Bothell, WA 98011