Many universities and other research organizations are using the sysmoBTS product line. It is a very small, low-cost all-in-one solution for running a small GSM/GPRS network for a variety of applications, including:
teaching GSM architecture and protocols
practical lab exercises for students learning about mobile communications
demonstration of GSM security problems
mobile malware research
tracing GSM protocols in real time for analysis
In a step-by-step approach teaching GSM/GPRS networks using the sysmoBTS, you can:
simply use the GSM NITB (network in the box) to operate a private network for teaching about mobile architecture.
change various GSM parameters to demonstrate their effect on system performance.
use the extensive built-in logging and introspection features to explore the current system state, channel usage, ongoing transactions, measurement reports, etc.
use wireshark to take protocol traces of the Um, Abis, A, Gb or Gp interfaces to interactively show signalling transactions and payload for Mobility Management, Voice, SMS and GPRS data service
review implementation of the various protocol layers and implementations of the functional elements of BTS, PCU, BSC, NITB, SGSN and GGSN.
actually extend the existing functionality by being able to alter any part of the code from Layer2 of the BTS upwards - it is all Free / Open Source Software!