I am not experienced in networking and I don't know too much about our
We have devices (further DEV) which are currently connected to the
server by PPP by modems and telephone lines.
There are several types of connections. The most important is that
DEVs have secure socket server and also a web server.
It is not possible to make any changes in DEVs.

Now we would like to replace telephone lines by small devices (SDEVs)
connected to the DEVs by PPP by a serial cable and connected to the
server by GPRS - UDP. My idea is that SDEV would start PPP
communication and then catch PPP packets from the serial line and send
them to the server by UDP through GPRS connection. There would by a
program on an server listening for packets from SDEVs which would
remove the PPP frame and replace it by Ethernet frame and resend it
(somehow) through Internet. And do it also the opposite way. I think
that pppd does something similar?

My questions are:
1. Is there a ready solution which would help us to replace telephone
lines by GPRS?
2. Could a solution that I tried to describe work?

I would very appreciate any suggestions and comments.

Thanks a lot,