styer@ms.uky.edu (Eugene Fred Styer) (02/14/91)
I have a situation where I want to thansfer some binary files home, but the network between the modem and the system uses causes xmodem to fail. I can get Kermit to work, but it runs only about 1/3 the speed my modem is capable of. So, does anyone know of a protocol that doesn't rely on a lot of special characters, and also gets reasonable throughput? Send mail if you know about anything. Eugene Styer - 402 Wallace, EKU, Richmond, KY 40475 styer@eku.bitnet "A complex number consists of two parts, a real part and an imaginary part, where the imaginary part is as real as the real part if you can imagine that." -- Eugene Styer - 402 Wallace, EKU, Richmond, KY 40475 styer@eku.bitnet "A complex number consists of two parts, a real part and an imaginary part, where the imaginary part is as real as the real part if you can imagine that."
mjf@cunixb.cc.columbia.edu (Michael J Flory) (02/14/91)
Eugene Styer writes: >I have a situation where I want to thansfer some binary files home, but the >network between the modem and the system uses causes xmodem to fail. I can get >Kermit to work, but it runs only about 1/3 the speed my modem is capable of. >So, does anyone know of a protocol that doesn't rely on a lot of special >characters, and also gets reasonable throughput? Send mail if you know >about anything. It sounds like another communication protocol won't help, as the problem is the communication between the system (I gather you mean the remote system) and the modem. Maybe your remote system is allocating communication ports between you and other users and that slows things up. But since Kermit (at least the non-sliding-windows flavor) has to wait for confirmation before sending each packet, try setting the packet size to something longer than the usual 94 bytes. Then the whole turnaround process will have to happen less often and things should go faster. I think the maximum is 2000 bytes or 2K -- I set 2000 and it seems to give me about 2K (2048 bytes). The only problem might be if you have a noisy phone line -- the "cost" of resending a packet is higher then. Tho' I'm at Columbia, I'm *not* part of the Kermit team, so this is just my amateur shot at the problem. Good luck! Michael Flory (mjf@cunixb.cc.columbia.edu)
ruthenb@bgsuvax.UUCP (Joe Ruthenberg) (02/15/91)
Your best bet for getting files rapidly transfered from a UNIX based system to a PC is to use either LYNX, SEALINK, PUMA, or ZMODEM. Puma is the fastest PC protocal I know of, outstripping Zmodem by about 10-15% on average. However, it is so rare as to not even be worth mentioning, but your system may have it. However, almost all systems have Y-Modem and Zmodem protocals. Zmodem is by far better than Y-Modem, so use it if possible. Zmodem is a streaming protocal, using either 32 bit or 16 bit CRC's for error correction. I regularly transfer files from a vax 785 to my 386 using Telix 3.12a. I also use WinQVT on occasion, but prefer Telix. In any case, to use Zmodem on a Unix system, type sz <filename(s)> where filesname(s) is/are the files you want to send. sz * will also work. You can get more information by typing man sz or apropos zmodem. Another major advantage I forgot to mention about Zmodem is that if a file transfer is interrupted, Zmodem will continue where you left off, rather than sending the entire file again. This means that if your system crashes 359K through a 360K file transfer, resending the file will send only that last 1K. What a Godsend... Anyway, Zmodem is about 40% faster on my US Robotics modem than kermit, so expect good results. Joe Ruthenberg, Dept. of Physics and Astronomy, Bowling Green State University ruthenbe@einstein.bgsu.edu
stucki@math.fu-berlin.de (C. v. Stuckrad) (02/21/91)
styer@ms.uky.edu (Eugene Fred Styer) writes: >----shortened a bit------ >So, does anyone know of a protocol that doesn't rely on a lot of special >characters, and also gets reasonable throughput? Send mail if you know >about anything. > >Eugene Styer - 402 Wallace, EKU, Richmond, KY 40475 styer@eku.bitnet >"A complex number consists of two parts, a real part and an imaginary part, >where the imaginary part is as real as the real part if you can imagine that." We here too would REALLY like to know of a transfer-Protocol wich reaches through tools like UNIX-telnet(or rlogin) or over the UNIX pty/tty interface. The problem of 'hanging' (timeout) occurres even in kermit if I am logged in on some workstation and then connectet onto another via TELNET. Being not a UNIX-Programmer but SYSOP (only) I never foud out the real problem.