Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!bloom-beacon!mit-eddie!uw-beaver!blake!ogccse!cvedc!nosun!tektronix!psueea!parsely!percival!omen!caf
From: caf@omen.UUCP (Chuck Forsberg WA7KGX)
Newsgroups: comp.dcom.modems
Subject: Re: Telebits and uucp g-protocol
Message-ID: <783@omen.UUCP>
Date: 14 Jun 89 23:21:29 GMT
References: <335@nixtor.UUCP> <13751@ncoast.ORG>
Reply-To: caf@omen.UUCP (Chuck Forsberg WA7KGX)
Organization: Omen Technology Inc, Portland Oregon
Lines: 22

In article <13751@ncoast.ORG> allbery@ncoast.ORG (Brandon S. Allbery) writes:
:Why?  Because layering two packet protocols on top of each other guarantees
:throughput problems.  Telebit, by special-casing common protocols, avoids
:this transparently.

Almost, but not quite, transparently.  Enabling protocol spoofing for a
protocol typically interferes with the correct operation of other
protocols, so the spoofing is not quite "transparent".

What's more, the protocol spoofing wins only if the spoofing completely
understands the protocol in use.  My TrailBlazers don't understand Sliding
Window or Long Packet Kermit.  They Don't understand some forms of XMODEM,
and their YMODEM spoofing doesn't work at all with real YMODEM.

Finally, the throughput with Kermit, UUCP, or XMODEM spoofing does not
equal the throughput attained with ZMODEM without spoofing.

Chuck Forsberg WA7KGX          ...!tektronix!reed!omen!caf 
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
  Omen Technology Inc    "The High Reliability Software"
17505-V NW Sauvie IS RD   Portland OR 97231   503-621-3406
TeleGodzilla:621-3746 FAX:621-3735 CIS:70007,2304 Genie:CAF