The most recent and booming technology is the GSM (global syatem for mobile communication).It is a very wide topic and can cover 3 topics in itself..The topics that it can cover are as follows:
1] How call originates and terminates from mobile to landline and vice versa.
2] 3G systems
3]Roaming technology.
and at the end u can ofcourse mention its drawbacks as iits security is a major area of concern...
