Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ames!elroy!cit-vax!oberon!skat.usc.edu!blarson
From: blarson@skat.usc.edu (Bob Larson)
Newsgroups: comp.dcom.modems
Subject: Re: need help with xenix Kermit to PC procomm
Message-ID: <12172@oberon.USC.EDU>
Date: 15 Sep 88 02:35:06 GMT
References: <20302@neabbs.UUCP> <11744@oberon.USC.EDU> <620@wsccs.UUCP>
Sender: news@oberon.USC.EDU
Reply-To: blarson@skat.usc.edu (Bob Larson)
Organization: USC AIS, Los Angeles
Lines: 35

In article <620@wsccs.UUCP> terry@wsccs.UUCP (Every system needs one) writes:
>In article <11744@oberon.USC.EDU>, blarson@skat.usc.edu (Bob Larson) writes:
>> This isn't a horrible idea, but you should be warned that XMODEM based
>> protocols are sometimes will corrupt the data on a single noise
>> character, and are picky about the types of systems and communications
>> equipment they run on.

>Not if they are using a CCITT CRC-16!

How does CRC-16 in one direction get around the problem of a
bogus single-character ack packet sent recived from the other
direction?

A couple of people have assured me that ZMODEM does not have this problem.

>> All versions of kermit are able to transfer files to each other.
>Not true.  Try try talking to an IBM 4300 with MS-Kermit 1.0!
I concede.  However, none of the other protocols will work in this
case.  (At least with kermit, you can get or make a version that will
work.)

>> (ZMODEM or WXMODEM is faster than non-windowing kermit, but windowing
>> kermit is faster than XMODEM or YMODEM.)
>Windowing protocols require large buffers... Xenix has 128 bytes of
>buffer.
So do many non-windowing protocols.  Note that XMODEM's packet size
exceeds the 128 byte limit you mention.

>The main problem with a windowed 7-bit protocol is that there is no way
>to get out of a kernal-mode xoff

Complain to your OS vendor, this is not realy related to kermit.
Bob Larson	Arpa: Blarson@Ecla.Usc.Edu	blarson@skat.usc.edu
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