On available bandwidth in FDDI-based reconfigurable networks

Networks used in mission-critical applications must be highly fault-tolerant. The authors propose an FDDI-based reconfigurable network (FBRN) that can survive multiple faults. An FBRN consists of multiple FDDI trunk rings and has the ability to reconfigure itself in the face of extensive damage. They consider three classes of FBRNs depending on their degree of reconfigurability: N-FBRN (nonreconfigurable), P-FBRN (partially reconfigurable) and F-FBRN (fully reconfigurable). They analyze the performance of FBRNs in terms of their available bandwidth in the presence of faults. In mission-critical systems, it is not enough to ensure that the network is connected in spite of faults; the traffic carrying capacity of the network must be sufficient to guarantee the required quality of service. They present a probabilistic analysis of the available bandwidth of FBRNs given the number of faults. They find that a fully reconfigurable FBRN can provide a high available bandwidth even in the presence of a large number of faults. A partially reconfigurable FBRN is found to be an excellent compromise between high reliability and ease of implementation