Link to home
Start Free TrialLog in
Avatar of Kenny_Krupnik
Kenny_Krupnik

asked on

GPRS PPP disconnection problem

Hi,
I have an embedded device which we developed and we are trying to connect it to a GPRS network via a Nokia 6310i.

The embedded device has an RS-232 port running a TCP/IP stack over PPP (client) - which connects to the Nokia.

The embedded device now sends the appropriete AT commands and then we see that the PPP session starts with the GPRS network, and some information is negotiated such as PAP, magic number, etc. Suddenly (towards the end of the negotiation), the GPRS side (PPP server) sends a request to terminate and the embedded device of course agrees.

We replaced our embedded device with a PC Win2K as a PPP client and everything went OK. Thus we know that our SIM and AT commands are correct. Unfortunetly, we don't have a way to see the PPP negotiation messages between the PC and the other side.

Any help regarding why the GPRS side requested to terminate is very much appreciated.

-- Kenny
ASKER CERTIFIED SOLUTION
Avatar of jmsousa
jmsousa

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of software_elico
software_elico

The phone you are using is already GPRS enabled ,that means it has a TCP/IP stack.
The GPRS will take care of the TCP/IP and the PPP,So you only need a RS232 interface on your embedded device and you can directly connect to the Phone modem,Then start using the AT commands through a terminal software(HYPERTERMINAL) and it should be fine.

The steps are clearly stated in the site:
http://www.gsm-modem.de/gprs-tcp-ip.html

also for your queries you can check the link:
http://www.gsm-modem.de/tcp-ip-gprs.html
 
software_elico
Our externalcommands.jar application on TC45 has a 'netkeeper' class which keeps the GPRS link open.  More information on externalcommands.jar is at http://www.tdc.co.uk/gprs/tc45.htm