but i need to know to the principles behind the working of such technologies...
To know principles You have to learn principles, but before that You have to learn basics. If You're not interested in basics, then just get already build robot (like something from
Dr. Robot series) and simply write software for it to do whatever You want (You also need to have at least basic programming skills).
sorry i am a beginner to networks..
Robot You're talking about requires way more skills than understanding networking. Do You know how to program MCU? Have You ever built robot before? Can You solder? Can You produce Your own machined parts? Do You have good understanding of electronic circuits? Can You write programs for Windows/Linux/Android/iOS?
so can u post some tutorials for tat... because by browsing i couldnt find out the best way for long range control robot...
You weren't searching very well then
The web page I linked You to contains a link to Arduino 3G Shield tutorial. If You hope to find step-by-step tutorial on how to build
spy-bot controlled from mobile device with live video capability over 3G, I have to disappoint You and say that it's not very likely You'll find one. You should look for tutorials on basic things and then apply gained knowledge when building something more advanced (ie.
spy-bot controlled from mobile device with live video capability over 3G). If You've never built robot before - start with
$50 Robot or something similar. $50 Robot does not look sophisticated, however by building it You'll learn many things used to build Your super-duper-kick-ass spy-bot.
Good luck with it