Question : IPCP, LCP etc

Does anybody have an in depth article or web link or tutorial on this whole protocol and process? We are still trying to understand it, and need to know how it all communicates on the gprs network. Thanks in Advance.

Answer : IPCP, LCP etc

Probably the best place to start is with the RFC's

IPCP is included in the PPP rfc at www.faqs.org/rfcs/rfc1332.html
LCP is at www.faqs.org/rfcs/rfc1570.html

In relation to your question PPP/IPCP/PAP/CHAP/LCP are not actually carried over the GPRS network as such, your application uses these protocols to speak to your GPRS terminal but from there on a different set of protocols is used over the network.
I.E. Your GPRS terminal acts the PPP server.

If you are planing to implement this in a microcontroller you would be well advised to not re-invent the wheel.
If you have a small microcontroller have a look at www.ethernut.de for the Nut/OS operating system and PPP/IP stacks.
For a more powerful you might also consider ecos or linux.

Of course if you want or need to spend money there are other choices as well.

Another option is to ignore it all, these days almost all of the terminal manufacturers provide a TCP/IP stack built in, for example:-
http://www.m2mconnectivity.com.au/servlet/Display?p=48