Date: Fri, 28 Jan 94 04:30:02 PST
From: Advanced Amateur Radio Networking Group <tcp-group@ucsd.edu>
Errors-To: TCP-Group-Errors@UCSD.Edu
Reply-To: TCP-Group@UCSD.Edu
Precedence: Bulk
Subject: TCP-Group Digest V94 #25
To: tcp-group-digest
TCP-Group Digest Fri, 28 Jan 94 Volume 94 : Issue 25
Today's Topics:
GPIB and packet
jnos gateway
MTU, TCP MSS, TCP WIN
New NET/Mac (hamradio TCP/IP) for the Macintosh
TPC MSS and TCP WIN per port
Send Replies or notes for publication to: <TCP-Group@UCSD.Edu>.
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Archives of past issues of the TCP-Group Digest are available
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We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
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Date: Thu, 27 Jan 94 16:33:29 CST
From: garnier@sol.med.ge.com (Dave Garnier x7-4286)
Subject: GPIB and packet
To: tcp-group@ucsd.edu
*>FYI -
*>
*>The Circuit Cellar BBS has a parallel to GPIB adapter info and SW
*>
*>GPIBLPT.ZIP
*I tried to look for it with archie but could not find any references.
*Could you put it somewhere where I could ftp this file from.
Could some kind soul post the fone number to this group?
Thanks much!
dave garnier
wb9own
ge medical systems, milwaukee
garnier@sol.med.ge.com
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Date: Thu, 27 Jan 1994 08:22:14 -0500
From: Gary Skuse <grsk@troi.cc.rochester.edu>
Subject: jnos gateway
To: TCP-Group@UCSD.Edu
I am running jnos on a dos box which is connected to a landline by a serial
port and to our University's extended LAN via an ethernet connection. I
would like to set up a gateway between the two so that I can call in by
telephone and get out over the Internet. I can figure out how to telnet
but I can't ftp. Has anyone done this? I would appreciate any suggestions
anyone has to offer. Eventually I would like to do something similar at home
so that I can access my ethernet network at home via the telephone from
work.
tnx and 73, ka1njl
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Date: Thu, 27 Jan 1994 10:31:25 -0800 (PST)
From: uswnvg!tconboy@uunet.UU.NET (Terry A. Conboy)
Subject: MTU, TCP MSS, TCP WIN
To: uunet!ucsd.edu!tcp-group@uunet.UU.NET
It seems that there is a minor confusion about these parameters. My
(probably meager) understanding is that your MTU determines the biggest
datagram that you send (allowing for 40 bytes of TCP/IP overhead) and
that MSS and WIN control what is sent TO you. In other words, if you
are sending mail or files to another host, your MSS and WIN have no
effect on what you send out to them.
I have a PC with a 1200 bps KISS TNC and a 2400 bps SLIP link. I set
the MTU on the TNC to 296 since the radio path is sometimes
marginal to some stations I communicate with. I set the MTU on the SLIP
to 1064 to allow big datagrams to be sent to my computer at work
over a 2400 bps dialup. I set TCP MSS to 1024 and TCP WIN to 2048 to
allow up to 2 datagrams to be outstanding without an ACK.
This works well in practice, since the congestion window (Cwind)
typically gets adjusted down to the MTU-40 of the station at the other
end of the radio link very quickly. So for me, having MSS or WIN per
port isn't very important. However, it does require that the station at
the other end of a radio link be intelligent in setting his MTU on the
radio port.
I've gleaned this from reading the docs, watching lots of traces, and
looking at the 'socket nnn' displays. If there's a flaw in my
reasoning, let me know.
73, Terry
--
Terry Conboy email: tconboy@uswnvg.com
U S WEST NewVector Group packet: n6ry@n7ipb.wa.usa
3350 - 161st Ave SE, MS 571 office: (206) 450-8388
Bellevue, WA 98008 fax: (206) 450-8399
------------------------------
Date: Thu, 27 Jan 1994 10:13:03 +0100
From: adam@igg.tno.nl (Adam van Gaalen PA2AGA)
Subject: New NET/Mac (hamradio TCP/IP) for the Macintosh
To: ham-digital@ucsd.edu, tcp-group@ucsd.edu
The Netherlands, January 25, 1994.
Hello dear reader,
Today I distributed the file NET_Mac2.3.35.sea.hqx...
In this version of NET/Mac I implemented the following:
- New <dayofweek> parameter for 'perform' command
- New: 'reboot_on_bad_date' } These new commands were implemen-
- New: 'sourcewhendone' } ted to make it easier to maintain
- New: 'resetsmtpto' } an unattended slip-telephone-link
- Improved the generation of dynamic aliases
- Some more 'enhancements' for q-and-d AppleTalk-fix
- Some more 'enhancements' for q-and-d fix
This version obsoletes all versions of info-mac/comm/radio-netmac in the
Sumex-Aim archives.
The new NET/Mac has been uploaded to ucsd.edu, to the directory
/hamradio/packet/tcpip/incoming. If it's not there (anymore),
then look at /hamradio/packet/tcpip/mac.
Kind regards,
Adam PA2AGA (e-mail: adam@igg.tno.nl )
( or: pa2aga@igg.tno.nl for letters only, NO BIG files here)
------------------------------
Date: Thu, 27 Jan 94 07:04:23 CST
From: Jack Snodgrass <kf5mg@kf5mg.ampr.org>
Subject: TPC MSS and TCP WIN per port
To: tcp-group mailling list <tcp-group@ucsd.edu>
Someone posted a message or sent me a note saying that they had fixed
JNOS to allow a MSS and WINDOW value to be asinged to each port. I forgot
who it was, but they said that they'd post the changes this week. I'm
anxios to see the code. I've tried setting the MTU on the port to less than
the TCP MSS and I'm not happy with the results. Stuff seems to go smoother
when I just reduce the MSS for the entire system rather than reducing the
MTU for a single port. I see packets being broken up into mtu size pieces
but NOS doesn't seem to re-assemble them and acknowledge them all the time.
I'm not familiar enough with the process to figure out what's wrong, but
I did see the same group of MTU sized packets be sent several times and
never ack'd by the receiving system. Anyway... I'd like to mod the code
to use a MSS and WINDOW based on the port. At least in my enviornment,
stuff does not change from port to port so that should not cause a problem.
Thanks.
73's de Jack - kf5mg
Internet - kf5mg@kf5mg.ampr.org - 44.28.0.14
AX25net - kf5mg@kf5mg.#dfw.tx.usa.noam - home (817) 488-4386
Dialup - kf5mg@tcet.unt.edu - work (looking for)
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End of TCP-Group Digest V94 #25
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