Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!ames!mailrus!sharkey!oxtrap!mudos!mju
From: mju@mudos.ann-arbor.mi.us (Marc Unangst)
Newsgroups: news.admin
Subject: Re: List of sites with broken Followup (No References) Software
Message-ID: <412.24749846@mudos.ann-arbor.mi.us>
Date: 19 May 89 22:32:07 GMT
References: <318@xdos.UUCP>
Reply-To: mju@mudos.ann-arbor.mi.us
Organization: A neat desk is a sign of a crazy person.
Lines: 41

In article <318@xdos.UUCP>, doug@xdos.UUCP (Doug Merritt) writes:
 >In article <89.247289F5@jsheese.FIDONET.ORG> jeffery@jsheese.Fidonet.ORG 
 >writes:
 >>Well, almost.  Most Fidonet mail transfer programs are able to use Zmodem
 >>file transfer which beats the heck out of G protocol.
 >
 >Why is it better?

1. It is a streaming protocol, so it doesn't wait for ACKs before sending
the next block.
2. It is an ACK-less protocol, so you don't waste your time confirming
to the sending machine that yes, we did receive that last block okay,
and that it can please send the next one.
3. It has dynamic block size adjustment.  If it's a clean line (few or no
errors), the block size can go up as far as 8K on a 9600 bps or higher
link.  If it's a dirty line, Zmodem will gradually decrease the block
size as it gets more and more errors, so there is less to retransmit in
the case of a line hit -- All the way down to 64 bytes on a very dirty
line.

Because 'g' always uses a fixed block size of 64 bytes? 128 bytes?, it
wastes a lot of time with ACKs on a clean line.  Yes, you can increase
the block size, but that means that you have more to transmit when you
get a line hit.

'g' was a good protocol 10 years ago, when it was first introduced.  It's
getting too old, and too slow in today's world of Trailblazer modems.
Who'll be the first to support Zmodem in their uucico?


 >        Doug
 >-- 
 >Doug Merritt            {pyramid,apple}!xdos!doug
 >Member, Crusaders for a Better Tomorrow         Professional Wildeyed 
 >Visionary
--  
Marc Unangst
UUCP smart    : mju@mudos.ann-arbor.mi.us
UUCP dumb     : ...!uunet!sharkey!mudos!mju
UUCP dumb alt.: ...!{ames,rutgers}!mailrus!clip!mudos!mju
Internet      : mju@mudos.ann-arbor.mi.us