What type of distribution for packet delay in a global network should be used in the control theory?

Andrei M. Sukhov N. Yu. Kuznetsova What type of distribution for packet delay in a global network should be used in the control theory? http://arxiv.org/abs/0907.4468 2009 CoRR abs/0907.4468 db/journals/corr/corr0907.html#abs-0907-4468