sion speed R, taking into account also the tag added to the packet by the bus access point to direct it to the correct output and that we assume to be made by NH bytes. The time slot length is thus ts = (np + nH)/R. Each bus access point simply transmits every packet arriving at the head of the input queue as soon as the synchronization is realized. No communication exists between dif- ferent access points. If it happens that combining the arrival time of different packets and the time needed to synchronize and transmit them, they overlap in time, a collision happens. In this case both packets are completely ruined, condition that can be revealed at the receiving point via a suitable error detection code inserted in the packet tag. Generally, the nth access point is integrated within the same chip with the nth detection point, SO that all the information on the sending activity from the nth input is shared with the nth detection point. Thus, when the nth detection point individuates a collision in the time slot where the corresponding access point has placed a packet, it can immediately send the information to the access point that selects a random waiting time and then retries the transmission. The random waiting time is used to decrease the probability of reiterated collisions between the same access points. In order to evaluate the maximum throughput, let us now image that the offered traffic is SO high that in any case there is always a packet waiting for transmission at each of the input switch fabric queues and that the probability that a bus access point transmits into a given time slot is p [29,30]. The probability that k access points among the N contemporary transmit in the same time slot is, thus, a binomial distribution that writes Telecommunication Networks (7.11) The relative throughput n coincides with the probability P that an access point transmits its packet successfully that is the probability that it is the only access point to transmit in the time slot. Thus, n=Np(1-p)(N-1) (7.12) A packet ar