There was a multicast (server to multiuser) protocol developed a few years
ago by John Hansen.

"HamWeb: Rethinking Packet Radio", John Hansen, WA0PTV,
SUNY Fredonia, Proceedings of the 16th ARRL/TAPR Digital
Communications Conference (Baltimore, 1997) pg. 41-47.

He distributed the software on the TAPR website.

-- Tom





"psyshrike" wrote in message
oups.com...
Awesome information!

What I am working on is really the development of a transmission
standard for some data that has some fairly specific requirements. It
is multuser to multiuser, with the server side being internet based and
the client side being simplex wireless. The setup is probably similar
in practice to how pagers are used now, except that there is a custom
presentation layer. Each client recieves more data than does a pager,
but the number of unique clients is far less, say less than 256
different client identities, with potentially thousands of replications
of each identity.

A proxy is at the center of the whole thing sort of like this:

WebBrowser-Internet-WebServer-Database-PresentationLayerConversion-Internet-Proxy-Radio-Wireless-Client

Multiuser write, multiuser read, where the proxy is a basically a
packet stripper. The reciever side does need to be able to
differentiate between different destinations like a pager. So it made
sense to me to just just use IP multicast addresses as wireless client
addresses, and then the proxies could recieve on the same multicast
addresses, manipulate the packet, and bridge it straight onto the
serial interface. Basically I could IP/multicast internationally over
the Internet, and then sprout wireless nodes from regional base
stations without having to do any address conversion.

So the radio/modem buffers the bits, and for a fully variable spectrum
selection I should look at RDFT. Linux would be the obvious choice for
development because of the amount of available driver code.

Tons of great information! I will study it and get back to you!

-Matt