On the Behavior of Hubnet with Applications to Priority Implementation

We study and analyze the behavior of Hubnet. A simulation model is developed from which the effect of the retry time on the performance of Hubnet is studied. Results show that increasing the retry time does not always mean higher delay. We show that, for retry time values that are less than and are factors of the packet length, the mean delay is better than some lower retry time values subject to some range. Also, we show thas contrary to what was believed earlier [llr]. a packet in a Hubnet with retry time which is a factor of the packet length is guaranteed transmission rights. We apply these results in studying a Hubnet with two priority classes, where the retry times are used for priority assignment. It is shown that a lower retry time does not always mean higher priority. Indeed, we show that a class of users with a retry time value that is a factor of the packet length could have higher priority than a class of users with a lower non-factor retry time value.