[comp.sys.ibm.pc.misc] what is the quickest

jimf@pro-gateway.cts.com (Jim Ford, Co-SysOp) (11/29/90)

In-Reply-To: message from tony@scotty.dccs.upenn.edu

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CS-ID: #347.ibm/csip.net@pro-gateway, 1223 chars
Date: 27 Nov 90 22:24:25 GMT
From: tony@scotty.dccs.upenn.edu (Anthony Olejnik)
Subject: what is the quickest (most efficient?) File xfer protocol?

I've been downloading some files from BBS lately using a 1200 baud modem.
I've been using Xmodem (CRC) mainly.

I'd like to know what file transfer protocol is best for transferring
a single file (as opposed to multiple files).

Since I'm using Procomm, I'm limited to the following:
	XMODEM
	KERMIT
	TELINK
	MODEM7
	YMODEM
	YMODEM batch
	ASCII
	COMPUSERV B
	WXMODEM

Also, some BBS support some file transfer protocols that are not contained
(by default) in Procomm (v2.4.2).  I understand that its possible to add
additional protocols to Procomm somehow (though I never really followed
thru on this).

So, what is the fasted (ie. uses up less connect time - assuming a clean
line)?

Any help would be *GREATLY* appreciated.

thanks.

--tony
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I'm not sure whether this will work anywhere or with anyone, but Compuserve B
is a very fast and efficient protocol.  You may, however, have to be connected
to CIS to use it.

===============================================================================
ProLine: jimf@pro-gateway
Internet: jimf@pro-gateway.cts.com
UUCP: crash!pro-gateway!jimf
ARPA: crash!pro-gateway!jimf@nosc.mil
BITNET: jimf%pro-gateway.cts.com@nosc.mil
====================Pro-Gateway 214/644-5113 3/12/2400 baud====================

ftw33616@uxa.cso.uiuc.edu (Frank T. Wang) (11/30/90)

That's odd.... I've had zmodem go all the way
down to 1 byte, & then had it creep back up to the great 1K blocks.......

I've heard that Xmodem G is even faster then Zmodem!  is this true?

kdq@demott.COM (Kevin D. Quitt) (12/01/90)

In article <1990Nov30.023420.6538@ux1.cso.uiuc.edu> ftw33616@uxa.cso.uiuc.edu (Frank T. Wang) writes:
>
>That's odd.... I've had zmodem go all the way
>down to 1 byte, & then had it creep back up to the great 1K blocks.......
>
>I've heard that Xmodem G is even faster then Zmodem!  is this true?


    Maybe it depends on whose ZMODEM you're using.  We use OMEN Technologies,
the latest version.  On a 38400bps line, kermit transfers average 2420 bytes
per second, ZMODEM averages 3664.  How does XMODEM G stack up?


-- 
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Kevin D. Quitt         demott!kdq   kdq@demott.com
DeMott Electronics Co. 14707 Keswick St.   Van Nuys, CA 91405-1266
VOICE (818) 988-4975   FAX (818) 997-1190  MODEM (818) 997-4496 PEP last

                96.37% of all statistics are made up.

brian@cunixf.cc.columbia.edu (Brian Hoffman) (12/01/90)

In article <3765@bnr-rsc.UUCP> lalibert@bcarh188.UUCP () writes:
>My brother once set up a download using ZMODEM.  He came back an hour
>later expecting to be logged out.  (Autologout when download completed.)
>But the modem was still chugging along with a block size of 1 byte!
>He quickly brok out and used XMODEM.  Turns out if ZMODEM feels too many
>errors are occuring it decreases the block size to reduce retransmission
>time.  But if the trouble clears up, it doesn't increase the size.
>What likely happened is the phone got picked up, giving mega noise, and
>dropping the block size.


Wrongo.  Zmodem will automatically increase the block size if the errors
go away.  Most likely, your brother was using a crummy unix implementation.


|Brian Hoffman								|
|brian@cunixf.cc.columbia.edu						|
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