Conference 7.286::digital

4825.0. "Modem setup for XMODEM, YMODEM and kermit protocol" by HGOVC::LKLEE () Tue Sep 03 1996 22:29

	Hello,
	
	I don't know if I can ask this question in this note file or not.
	If not, please advice the proper notes file to me.

	My customer needs to do the file transfer between PCs and central 
	server via telephone network. The file transfer protocols XMODEM, 
	YMODEM or kermit can be used. If no data compression and data 
	correction ( V.42bis, MNP... ) is implemented in the modem, transfer 
	can be done successfully.  Due to the line quality and we want to 
	improve the throughput of telephone line, we set up the modem 
	to implement data compression and data correction features.
	After we implemented data compression and data correction features 
	in the modems, the files can not be transfer between PC and central 
	server successfully most of the times.  May be due the the profile 
	of the modem was not setup properly.

	Please advice if the file transfer protocols ( XMODEM, YMODEM
	and kermit ) can work with the data compression/correction
	methods of the modem.   

	XMODEM, YMODEM or kermit protocol is the only choice for doing 
	file transfer for this customer.  Since I am not good at modem
	setup, please advice what parameter should be set in the modem
    	or give me a sample modem profile for reference.

	Thanks in advance + regards,

	LK Lee


                                                        

>    Please advice if the file transfer protocols ( XMODEM, YMODEM and
>    kermit ) can work with the data compression/correction methods of the
>    modem. 
    
    SOLVIT::MODEMS, VMSZOO::KERMIT, and NOTED::IBMPC-93 are more
    appropriate conferences, but yes, they do work. Note that compression
    may actually slow things down slightly if the file you are transferring
    is already compressed. Make sure that:

    	a) you have speed buffering enabled or built into your modem
    	b) your port speed is at least 2X your connect speed for MNP
    	   compression or 4X for V.42 compression
    	c) you are using hardware (RTS/CTS) flow control, and not XON/XOFF
    	d) your PC's UART can support the port speed you select (a 16550 UART
    	   is necessary for port speeds above 9600 or 19200).
    
    -Tom

If you have TCP/IP network, the easiest way to transfer files to/from the 
PC is via a PPP network connection.  Windows95/NT includes FTP to transfer 
files, or you can use Netscape.

							-Paul