Hi Andy

I started typing this and realised you said "packet" protocol. Thought I'd
leave it in (below) anyway!

- Assuming you want max throughput on a dedicated channel and dont care
about long TX times
- Make sure your maxframes is something huge (7 is max)
- Get your paclen as long as you can. Although 255 is the normal maximum I
did some experiments at 768 some years ago (max for my TNC2 in KISS mode)
- Get your TXDelay and TXTail as small as it can go.
- Make sure your error rate from low signal/interference/over deviation etc
is nil
- Compress the data stream (grin)

Kiss mode by itself doesnt give you better throughput. It simply makes the
TNC a little more "dumb" and allows the host to control it more/better.
TCP/IP (I think) over packet adds a little more overhead to the packet
length so AX25 "connected" mode is likely to be a little faster. I use to
play packet a lot but not for a while. Cant quite remember it all sorry!

I havent seen any implementations using KISS try and send raw data (ie not
AX25 in some form) but I guess that you could certainly modem out a data
stream and have some kind of error correction built into the boxes at each
end. You might be able to use the EC in file transfer protocols like ZModem
but it may get upset at not having a full duplex connection. Might be an
interesting piece of code to write.

Sorry for being short on this. Ask if you want more info.

Cheers

Bob VK2YQA


================================================== ===============
Have a look at Wyman1x. http://www.svs.net/wyman/examples/hdsstv

It is a one way digital code stream with redundancy/checksums built into the
stream. You encode a binary file to a WAV then play it through your radio.

The page above looks like a SSTV piece of sowftare but you can send/recxeive
any kind of digital data. There are some graphs on throughput etc possible

There is code for both Windoze and Linux available

I'm very new to packet radio/digital communications and am trying to climb
up the learning curve too fast. It hurts :-) My question is: What
protocol/mode will give me the best data throughput using 9600 baud packet
on VHF or UHF? Using standard AX.25 protocol in connected mode I'm able
to
achieve about 1000 baud throughput. Unconnected I can get about 4000
baud,
but of course that is without any error checking or correction. I'd like
to get maximum data transfer between two stations...network operations are
secondary. I'm guessing using KISS mode would allow me to get better
throughput because of the lack of AX.25 overhead, but I'm pretty clueless
on
how to actually do anything with KISS mode. How do I implement something
like TCP/IP over radio? Is that any better than AX.25? Less overhead?
I've downloaded JNOS, but I'm not sure what exactly it is or what to do
with
it. Any suggestions or help would be appreciated. I've searched the web
for info on running different protocols in KISS mode, but everything I
find seems like it was written for computer scientists in the 1980s.

Thanks!

Andy KB9JOZ

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