Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!faatcrl!dynalogic!jprad
From: jprad@dynalogic.UUCP (Jack Radigan)
Newsgroups: comp.sys.amiga
Subject: Re: Question about a possible transfer protocol
Message-ID: <18302df1.ARN0005@dynalogic.UUCP>
Date: 11 Nov 90 02:11:13 GMT
References: <45220@eerie.acsu.Buffalo.EDU>
Reply-To: jprad@dynalogic.UUCP
Followup-To: comp.sys.amiga
Organization: Dynalogic Product Support
Lines: 28

In article <45220@eerie.acsu.Buffalo.EDU>, Richard B Wicks writes:

>	I was thinking late at night on how I could make a brand new and really
>fast transfer protocol.  This is (I think) a completely new idea.  It occured
>me that the only way to really speed up a transfer is the have the receiving 
>computer send NO information back to the sending computer.

   ZMODEM (full streaming) and YMODEM-g both operate in this fashion.  With
ZMODEM, it only sends a reposition header to the sender when a data frame is
recieved in error.

   YMODEM-g requires an MNP or similar error-corrected connection since it
only checks for errors, it does not correct for them.  It also requires full
256 byte transparancy as do all XMODEM technology protocols.

>	My question:  would this speed up transfers?  It seems to me that it
>would have to if you programmed to protocol to take advantage of the
>multitasking ability of the Amiga.  The only problem is getting some poeple
>to adopt the protocol.

   YMODEM-g will give you some great throughput figures, 98+% is quite
common.  ZMODEM, since it is compatible with packet-switched networks,
is somewhat slower due to the necessary character escaping it has to do
to prevent network problems.

>-Rich

 -jack-