Hi,
First of all very sorry for late reply. I was involved in major delievry of a software.
Well as far pdf file is concerned, It explains the mobile attachment procedure in GPRS setup. Whenever a mobile comes up (i.e. we switch on our mobile), then this procedure starts. In very first step MS sends it's details to BSC which includes it's TMSI, MNC, MCC, LAC, RAC. BSC further passes this details to SGSN. I hope you are well aware that in GPRS SGSN and GGSN are two new entities which make sure minimum changes in a GSM setup.
These entities further checks identity and authenticate MS details. After various checks Location update procedure starts and so the current location of MS is updated. This ends the mobile attachement procedure.
After Mobile attachement PDP context activation process starts. PDP(Packet data protocol) context is a datastructure present on both the SGSN and the GGSN which contains the subscriber's session information . When a mobile wants to use GPRS, it must first attach and then activate a PDP context. This allocates a PDP context data structure in the SGSN that the subscriber is currently visiting and the GGSN serving the subscribers access point.
I have taken the reference from eventhelix . com and wikipedia . org
I will be glad to cotinue the discussion in case of any issue.
Thanks and regards.
Gaurav Bhatnagar