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Old February 13th 06, 04:06 AM posted to rec.radio.amateur.digital.misc
Bob Bob
 
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Default Can't run TCP/IP through AX.25 using Linux

If I may answer first...

TCP/IP is suppose to self calculate retry etc periods based on the first
few packet failures. I am surprised you are having problems with the
link at all. Perhaps some massaging of the TCP retry parameters might be
in order. I'll admit I dont know where to do that in Windows without
looking it up. It will be as registry setting.

I wonder if you are also using plain serial ports at each end or some
kind of ethernet converter. That can mess things up as TCP/IP thinks it
has a faster throughput speed than it really doesnt. The other
possibility is that serial hardware handshaking is broken although FTP
would be affected by that. (Depends on the direction and which end has
failed though) Lowering your DTE speed may also help.

As a simple workaround you can limit the number of concurrent http
requests your browser will allow. Once again I dont know how this is
done in IE but Firefox has a about:config parameter
network.http.maximum.connections or similar. The end effect will be that
web pages with lots of internal lnks (eg pictures) will tend to load
more one after the other than bits at the same time. Email, FTP and
telnet use a port for each direction whereas web browsers can use 100+
source ports to get a web page.

If you wish to try this and dont have Firefox, download it and gimee a
shout and I'll walk you through the config changes.

I have also heard the SLIP might be a better way to go over these links
because of the half duplex factor. I'll admit I havent tried this but it
wont hurt to try. W2K and above have SLIP available if you want to play
with it.

Strangely I am thinking of using a 900MHz serial link to my mother in
laws house. The reason I am not using 802.11 Ethernet is path obstructions.

One option by the way, if you want to throw lots of money at it, is to
setup a second link such that the whole things runs a "real" fullduplex.

Lastly I havent checked around on the web on this topic. Perhaps others
have had this issue and found a solution.

Cheers Bob

Braath Waate wrote:

I've been running the ConnexLink 900 Mhz serial modems for over a year
now to connect my house network to my business network in a rural area.
The networks are Windows based and the link runs PPP using the
radio's full duplex setting.