Two-terminal Reliability Analysis for Time-evolving and Predictable Delay-tolerant Networks

Background: Several techniques are available to evaluate the two -terminal reliability (2TR) of static networks; however, the advent of dynamic networks in recent past, e.g., Delay Tolerant Networks (DTNs), has made this task extremely challenging due to their peculiar characteristics with an associated disruptive operational environment..Recently, a Cartesian product -based method has been proposed to enumerate time-stamped-minimal path sets (TS -MPS) -a precursor to compute the 2TR of such networks. However, it cannot be used to generate time slumped-minimal cut acts (TS-MCS). TS-MCS cannot only be used as an alternative to generate 2TR but also to compute other unexplored reliability metrics in DTNs, c.g., the weakest link Objective: To propose a novel approach to enumerate both TS -MPS and TS-MCS of a dynamic network, thereby computing the 2TR. of such networks. Methods: The proposed technique converts the time aggregated graph model of a dynamic network into a Line Graph (LG) while maintaining the time -varying graph's node reachability information. This LG is used thereafter to generate TS-MCS as well as TS -MPS to compute 2TR of the net Work. Results: The DTN examples are presented to show the efficacy and salient features of our algorithm to obtain 2TR of such networks. Conclusion: The terminologies and techniques used for studying/analyzing network reliability of static networks can be extended to dynamic networks as well, e.g., the notion of minimal path sets to TS -MPS or minimal cut sets to TS-MCS, to assess their network reliability a potential area of furthering network reliability research.