From: TURTLE              
To: KNIGHT OWL          
Subject: protocols      
Date & Time: 02/20/91 17:46:07
Message Number 12372

XModem 1K is normal XModem/CRC with 1024-byte packets (generic
XModem uses 128-byte packets). YModem is XModem 1K with an additional
packet that gives the name of the file being transmitted; it is
also a batch protocol, so you can send or receive a large number of
files all at once (when one file is finished transmitting, it will send
an EOT followed by a block zero containing the filename of the next
file to be sent; it uses two EOT's to end the transmission when all the
files have been sent). XModem 1K is, obviously, faster than XModem
because the packet size is larger. Its reliability is about the same,
but on noisy lines you're better off with XModem since you don't have
as much stuff to retransmit if a frame gets trashed.