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Re: internet feeds


Here is some more info on my metaserver. First of all the server is
a slightly modified version of a dataserver application that we use
here at GSFC in out IP-in-Space activities (see
http://ipinspace.gsfc.nasa.gov ).
It listens on a UDP port for telemetry frames and spits them out over
TCP connections to whomever is connected. It doesn't know or care what the
data is. 

Right now the intention is to just provide a centralized datastream for
P3T compatible applications. I have seen Phil Karn's proposed standard for
distributing TLM data over the internet. I think it is a great idea but
my server application doesn't care. It is P3T, or a compatible data source
that would have to put the appropriate header info in the packets.

There are actually two applications involved in my project. The first one
is the dataserver itself. The second is a bit of "glueware". P3T and its
compatible apps act as servers, i.e. they expect someone to connect to
them on a TCP socket. My dataserver expects to receive UDP packets. I have
written a simple application that needs to be run on any computer that
intends to be a data source. After you run P3T (or IZ8BLY's demod for example)
you then run my app. It connects to P3T as a client, receives the TLM
frames on the TCP socket, and sends them to the Goddard server as UDP packets.

I suspended work on the project temporarily due to the holidays and the 
unknown status of AO-40. I only have one more bug to fix before I put it
online and make the 'glueware' UDP converter available. Hopefully I can
squeeze it in during these last few days of my vacation.

Testing the software is kind of tedious. I have one machine generating
test data out the sound card. I have another computer receiving the 
data via its sound card and demodulating it with IZ8BLY's demod. On that
same computer I am running my UDP converter and spitting out UDP packets
over my in-house ethernet. The dataserver is running on a linux box along
with tcpdump for inspecting the packet contents. Yet another computer
is running P3T and acting as a test client to connect to the dataserver.

I will keep everyone posted!
Ron, wa4sir

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