rreiner@yunexus.YorkU.CA (Richard Reiner) (06/26/90)
dmm0t@hudson.acc.Virginia.EDU (David M. Meyer) writes: >I've always found Zmodem to be the fastest. Kermit, on the other >hand, is consistently the slowest protocol of any I've used. There's Kermit and then there's Kermit. Old versions of Kermit are pretty slow: they use 90 byte packets, and handshake after each packet. Newer Kermits can use packets up to 2000 bytes, and support sliding windows. This means they can be as fast as Zmodem (and for the same reasons). There's also the issue of whether Kermit thinks it's on a 7 bit or an 8 bit wide link. Sending binaries on a 7 bit link forces Kermit to do "8th bit quoting" which on average increases transfer time by 50%. Other protocols, on the other hand, generally just can't transfer 8 bit data on a 7 bit link.
pfeifer@hpavla.AVO.HP.COM (Mark Pfeifer) (06/26/90)
>The subject line says it all. I'm wondering what is the fastest protocal >to use when transfering files over modem? Kermit, Xmodem, Zmodem, or >whatever. I normally use Kermit but I'd like to find something else maybe >a little bit faster. Anyway, let's hear some recommendations if anyone >has any. > - Jeff >-- > EMAIL: jharper@carina.unm.edu I'm not sure what the fastest is, but Kermit is certainly the slowest (short of typing it in). I normally use Zmodem, and average about 228-231 cps throughput on a plain 2400 bps modem. Zmodem also has better error checking then Kermit (CRC-32), and supports Crash Recovery (picking up a stopped file transfer in the middle). Mark pfeifer@hpavla.avo.hp.com HP Avondale Division
bruce@archive.rtp.dg.com (Bruce Kahn) (06/26/90)
In article <1990Jun23.203333.12501@ariel.unm.edu>, jharper@carina.unm.edu (Jeff) writes: |> The subject line says it all. I'm wondering what is the fastest protocal |> to use when transfering files over modem? Kermit, Xmodem, Zmodem, or |> whatever. I normally use Kermit but I'd like to find something else maybe |> a little bit faster. Anyway, let's hear some recommendations if anyone |> has any. |> - Jeff |> -- |> EMAIL: jharper@carina.unm.edu |> |> "A stitch in time takes up space.." |> The Doctor - "Delta and the Bannerman" You are opening up a very very big can of worms by asking such a vague question. Before the melee begins Id recommend you clarrify your request by stating what conditions you will be using it for (ie local calls, across campus, across the country, etc). Various protocols are great if you have very clean lines for transfering but will absolutely flop miserably when the quality goes down or you use services like PC Persuit (which packetizes your data w/o your concent/knowledge thus causing windowing and buffering problems at times). Another item to consider is what you will be using it for: single files, multiple files, streaming data, etc. Some protocols are designed with some of these in mind... These are just 2 things that you should consider along with all the suggestions you may/may not recieve... Bruce (bruce@archive.rtp.dg.com)
gwang@igloo.scum.com (George Wang) (06/27/90)
In article <1990Jun26.021616.11782@murdoch.acc.Virginia.EDU> dmm0t@hudson.acc.Virginia.EDU (David M. Meyer) writes: >In article <1990Jun23.203333.12501@ariel.unm.edu> jharper@carina.unm.edu (Jeff) writes: >>The subject line says it all. I'm wondering what is the fastest protocal >>to use when transfering files over modem? Kermit, Xmodem, Zmodem, or >>whatever. I normally use Kermit but I'd like to find something else maybe >>a little bit faster. Anyway, let's hear some recommendations if anyone >>has any. > >In my experience, the fastest file transfer protocol is Ymodem-G; the >catch is that it requires an error correcting modem (with MNP level >5, I think). For file transfers on a non-error correcting modem, >I've always found Zmodem to be the fastest. Kermit, on the other >hand, is consistently the slowest protocol of any I've used. > In MY opinion (and under test results) the fastest protocal under normal line conditions (long distance lets say) is ZMODEM MOBYTURBO... It's activated with the -m option and is only available after 2/14/90 I believe.. That stuff pretty much goes faster than Y-Modem G.. Plus on a error correcting modem (say HST) the line has to be pretty clean to get high results... I say Zmodem MobyTurbo is fastest.. Y-modem G is close and same but requires an very clean line on a HST 14.4K mode... -- George Wang Wang Associates (217) 332-4019 (Campus) -- (708) 470-0308 (Home) Email: gcw20877@uxa.cso.uiuc.edu (INTERNET), gargoyle!igloo!gwang (UUCP)
pfeifer@hpavla.AVO.HP.COM (Mark Pfeifer) (06/27/90)
>/ hpavla:comp.binaries.ibm.pc.d / roy@cybrspc.AVO.HP.COM / 2:55 am Jun 26, 1990 / >Personally, I get the best results from Zmodem. Typically 210 cps from >Telemate, 224 from DSZ and 227-230 from DSZ with MobyTurbo enabled. (all >these are at 2400 bps) >-- > Roy M. Silvernail | 'I don't see why you people | Opinions found > now available at: | seem to think this is magic... | herein are mine, > cybrspc!roy@cs.umn.edu | Its just this little chromium | but you can rent >(cyberspace... be here!)| switch here...[click]' | them. >---------- What's this MobyTurbo? =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Mark Pfeifer pfeifer@hpavla.avo.hp.com HP Avondale Division
porter@caip.rutgers.edu (Adam Porter) (06/27/90)
While Zmodem is unquestionably fast, mostly reliable, and widely supported, I have had slightly better transfer times with Puma and with HyperP. -- Adam Porter (porter@caip.rutgers.edu) C:\> alp
weisen@eniac.seas.upenn.edu (Neil Weisenfeld) (06/27/90)
In article <12085@yunexus.YorkU.CA> rreiner@yunexus.YorkU.CA (Richard Reiner) writes: >dmm0t@hudson.acc.Virginia.EDU (David M. Meyer) writes: > >>I've always found Zmodem to be the fastest. Kermit, on the other >>hand, is consistently the slowest protocol of any I've used. > >There's Kermit and then there's Kermit. Old versions of Kermit are >pretty slow: they use 90 byte packets, and handshake after each >packet. Newer Kermits can use packets up to 2000 bytes, and support >sliding windows. This means they can be as fast as Zmodem (and for >the same reasons). > >There's also the issue of whether Kermit thinks it's on a 7 bit or an >8 bit wide link. Sending binaries on a 7 bit link forces Kermit to do >"8th bit quoting" which on average increases transfer time by 50%. >Other protocols, on the other hand, generally just can't transfer 8 >bit data on a 7 bit link. Thanks goodness someone mentioned this. There was some dispute about this a while ago. Some people said that Zmodem doesn't do 8th bit quoting and some said that it does. I even had some alum. from my school try to tell me that I didn't need 8th bit quoting (even though the campus network administrators agree that I do). ... And someone else who told me that our VAX 6300 was stupid (or broken) because IT required it. I didn't take the time to respond to that. Anyway, If someone can truly answer whether or not Zmodem will do it, and if a version exists for UNIX that will do it, it would be greatly appreciated. Neil =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Neil I. Weisenfeld | InterNet: weisen@eniac.seas.upenn.edu Dept. of Computer and Info. Sciences | USPS: I dunno, I'm moving... University of Pennsylvania | PENNmail: Don't even try it... =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
poffen@sj.ate.slb.com (Russ Poffenberger) (06/27/90)
In article <8460002@hpavla.AVO.HP.COM> pfeifer@hpavla.AVO.HP.COM (Mark Pfeifer) writes: >>The subject line says it all. I'm wondering what is the fastest protocal >>to use when transfering files over modem? Kermit, Xmodem, Zmodem, or >>whatever. I normally use Kermit but I'd like to find something else maybe >>a little bit faster. Anyway, let's hear some recommendations if anyone >>has any. >> - Jeff >>-- >> EMAIL: jharper@carina.unm.edu > >I'm not sure what the fastest is, but Kermit is certainly the slowest (short >of typing it in). I normally use Zmodem, and average about 228-231 cps >throughput on a plain 2400 bps modem. Zmodem also has better error checking >then Kermit (CRC-32), and supports Crash Recovery (picking up a stopped file >transfer in the middle). > > Mark I can get about 238 CPS from compuserve using B-plus protocol. Or 780 CPS from ftp using SLIP between two 9600 baud modems. Russ Poffenberger DOMAIN: poffen@sj.ate.slb.com Schlumberger Technologies UUCP: {uunet,decwrl,amdahl}!sjsca4!poffen 1601 Technology Drive CIS: 72401,276 San Jose, Ca. 95110 (408)437-5254
roy@cs.umn.edu (Roy M. Silvernail) (06/28/90)
pfeifer@hpavla.AVO.HP.COM (Mark Pfeifer) writes: > >/ hpavla:comp.binaries.ibm.pc.d / roy@cybrspc.AVO.HP.COM / 2:55 am Jun 26, > >Personally, I get the best results from Zmodem. Typically 210 cps from > >Telemate, 224 from DSZ and 227-230 from DSZ with MobyTurbo enabled. (all > >these are at 2400 bps) > > What's this MobyTurbo? MobyTurbo is an accelerated transfer mode introduced in February's release of DSZ. Both copies of DSZ must be Moby-capable for it to work. See the DSZ docs for a more complete explanation. I just know that it seems to work faster than straight Zmodem. -- Roy M. Silvernail | 'I don't see why you people | Opinions found now available at: | seem to think this is magic... | herein are mine, cybrspc!roy@cs.umn.edu | Its just this little chromium | but you can rent (cyberspace... be here!)| switch here...[click]' | them.
roy@cs.umn.edu (Roy M. Silvernail) (06/28/90)
weisen@eniac.seas.upenn.edu (Neil Weisenfeld) writes: > Thanks goodness someone mentioned this. There was some dispute about > this a while ago. Some people said that Zmodem doesn't do 8th bit quoting > and some said that it does. [...] > Anyway, If someone can truly answer whether or not Zmodem will do it, > and if a version exists for UNIX that will do it, it would be greatly > appreciated. This is from the DSZ.DOC file included with DSZ0411: ------------------------------------- ZMODEM over 7 bit paths: (Not supported in DSZ.COM) A pair of ZMODEM-90 programs with 7-bit support operating over a 7 bit path should detect that fact and switch to one of two 7-bit path compatible encodings. For testing, this can be forced with a "-E" option. Default 7-bit mode is RLE compression and 8th bit quoting similar to Kermit but more efficient because not so many control characters are quoted. Use this default for text files. Rubout and all control characters can be escaped with the -e option. Individual control characters can be escaped with "zmtxesc" and "zmrxesc". Pack-7 instead of quoting is activated with the -P option. (-P has no effect on 8 bit paths.) Pack-7 packs 4 bytes into 5 printing characters. This is more efficient than quoting for files where 25% more 8th bits appear than the number of characters saved by RLE compression. (This statement applies to GIF, ARC, ZOO, and ZIP files. It may or may not apply to other binary file formats, depending on the data.) Pack-7 will match or beat standard Kermit on ZIP files, even when Kermit has use of all 8 bits. ----------------------------------------- The -E option also works with the Unix version (RZSZ0525), in my experience. -- Roy M. Silvernail | 'I don't see why you people | Opinions found now available at: | seem to think this is magic... | herein are mine, cybrspc!roy@cs.umn.edu | Its just this little chromium | but you can rent (cyberspace... be here!)| switch here...[click]' | them.
thorh@tekgvs.LABS.TEK.COM (Thor Hallen) (06/28/90)
Zmodem works fine for me on a 7 bit link. I haven't carefully compared speed on 7 bit vs 8 bit mode but there is no major difference. Certainly not a factor of 2. Thor Hallen Tektronix, Inc.
merlin@csvax.seas.smu.edu (David Hayes) (06/28/90)
In article <12085@yunexus.YorkU.CA> (Richard Reiner) writes: >>There's also the issue of whether Kermit thinks it's on a 7 bit or an >>8 bit wide link. Sending binaries on a 7 bit link forces Kermit to do >>"8th bit quoting" which on average increases transfer time by 50%. >>Other protocols, on the other hand, generally just can't transfer 8 >>bit data on a 7 bit link. and in article <26501@netnews.upenn.edu> (Neil Weisenfeld) writes: >Anyway, If someone can truly answer whether or not Zmodem will do it, >and if a version exists for UNIX that will do it, it would be greatly >appreciated. Rest easy, Neil. Zmodem has been running happily on my PC over a 7-bit link for six months, and it works just fine. Yes, it will quote 8-bit data. We have AT&T Information System Network (what a joke), which is basically an ASCII switch. It will transfer only 7-bit data, so I was stuck with Kermit until I found Zmodem. I've finally given up on that, but only because I got an ethernet card for my PC. David Hayes School of Engineering Southern Methodist University merlin@smu.edu uunet!smu!merlin "Here's a test to see if your job here on Earth is finished: If you're still here, it isn't." -- Richard Bach, _Illusions_
rogers@ux.acs.umn.edu (Brynn Rogers) (06/29/90)
For me Zmodem is the fastest when dealing with a BBS (I get 250 CPS or so with a 2400 Baud MNP5 modem. BUT, when talking to a unix system through a bunch of terminal servers, I find that Ymodem gives me a better throughput (210 CPS or so) compared to Zmodem (sz -l 512) which gives about 170 CPS. I wish I could get the same rates with the unix system that I get on my favorite BBS. I have been able to get >200 CPS from the new kermit on unix, but my unix account just changed and I don't seem to have access to the latest version of C-Kermit anymore. Getting these kind of rates from kermit requires you to have a .kermrc with the right parameters, Plus turning on the 8 bit stuff through all the boxes you go through, Plus possibly having the flow-controls set right through all the boxes. Zmodem and Ymodem are so much easier to live with. Brynn
glenn@ocsmd.ocs.com (Glenn Ford) (06/29/90)
In article <1769@ux.acs.umn.edu> rogers@ux.acs.umn.edu (Brynn Rogers) writes: >I find that Ymodem gives me a better throughput (210 CPS or so) compared >to Zmodem (sz -l 512) which gives about 170 CPS. > >I wish I could get the same rates with the unix system that I get on my >favorite BBS. I Run a Unix BBS, and Zmodem gives me about 230 CPS. What kind of Unix box are you talking about?
umrose05@ccu.umanitoba.ca (Dave Rose) (06/30/90)
rreiner@yunexus.YorkU.CA (Richard Reiner) writes: >jharper@carina.unm.edu (Jeff) writes: >Depends on what you're measuring. If total number of bytes moved is >the question, then BiModem is the fastest: on a 2400 bps line it can >move about 450 cps (yes, 450, that's not a typo), by doing two 225 cps >transfers simultaneously, one in each direction. Since the modems in >common use are full duplex, there are two channels available, and this >trick isn't so hard. All that's needed is a protocol which allows the >mixing of control information for one transfer in with the data for >the other. Very nice indeed if you need to move data both ways. Has anyone successfully created such a protocol? If so where is it available? Please reply via email. Dave (umrose05@ccu.umanitoba.ca) -- Dave Rose : Local (UnixWS) - UMRose05@CCU.UManitoba.CA P.O. Box 403 : Local (Amdahl) - #Rose05@CCM.UManitoba.CA Winnipeg, Manitoba, Canada: UUCP Node #005 - drose@trash.UUCP R2M-5H3 :