Connectability: a performance metric for reconfigurable transport networks

This paper presents a metric for managing dynamically reconfigurable transport networks. In such networks, one physical set of transport links can be configured into many different logical networks, in order to meet uncertain and volatile traffic demands. Connectability is a figure of merit for capturing the composite routing efficiency and capacity utilization of a transport network. Connectability is mathematically inspired by existing metrics for reliability. Reliability concepts are adapted to quantify notions of efficiency in reconfigurable networks. The authors define connectability mathematically, and set out a procedure for its´ calculation in a distributed real-time setting. The centralized version of this calculation has O(n log n) time complexity. A series of simulation studies are presented to illustrate the use of connectability in characterizing strategies for transport network reconfiguration. One strategy based on the isolated calculation of connectability at each node is shown to yield lower blocking and more efficient use of transport network resources than the other strategies tested. Finally, a short study of applying connectability to restoration in a national network demonstrates that there is a continuum along which restoration can be temporarily traded off against transport network management