I'd say with these basic requirements the two elements that should have a formal specification is what exactly you expect things to look like (as that may elimi

I'd say with these basic requirements the two elements that should have a formal specification is what exactly you expect things to look like (as that may eliminate some already existing libraries for this task) and what you mean when you say "the network adapts its layout". If you don't have specifics in mind for either of these two items, then there could be a lot of work going back and forth trying to figure out what the end goal actually is. I'd say it would be good to know what libraries might get used in this sort of application and a quick search get's a few lists of them pretty easily (e.g. http://stackoverflow.com/questions/7034/graph-visualization-library-in-javascript?lq=1 http://stackoverflow.com/questions/7034/graph-visualization-... )