Hello Vao,
As the packages go from the top layer to the physical the size of the actual package increases for each layer with a h header
the % of the bandwidth used by the headers*layers addons will always be the same
(only the _absolute_ number of bites represented by the headers*layers addons will vary as the _absolute_ number of packages varies)
Answer: n*h/(m+(n*h))
http://condor.depaul.edu/~jkristof/1999Aut463/1999Aut463-MidtermExam.txtRegards,
tdor