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Network coding allows to increase the throughput as well as the robustness of data transmissions. Regarding robustness, especially rateless network coding was shown to be beneficial. However, the vulnerability of mere network coding against attacks requires introducing security mechanisms, and as known, security implies costs. Within this paper, we evaluate the efficiency of secure network coding schemes applied in a rateless manner. Our results show that secure rateless network coding schemes can still outperform routing. The actual efficiency depends on parameters like generation size, packet size, or network topology. Since conflicting efficiency parameters cannot be fulfilled in equal measure, selection of a secure network coding scheme and its parameters should be done adapted to the actual communication requirements.

The utility of simulations depends on the confidence in the simulation implementation and its results. This study discusses the verification of the communication models in the parallel trace-driven simulation framework HAEC-SIM. As simulation input, a parallel application is executed and recorded on an existing HPC system. The simulation focuses on modeling the transfer times of point-to-point messages within the application and the indirect effects resulting in an output trace of application events of the simulated execution on a target platform. Consequently, via verification the message transfer times obtained with HAEC-SIM are compared with those of an independent implementation of the communication models. Both implementations consider the number of hops, the size and the target system parameters for each message. During verification the following factors are varied: application benchmarks, network topologies, mapping strategies, and resilient communication models.Verification yields an almost perfect agreement: the transfer times differ for a tiny percentage (0.00019 %) of messages by a negligible deviation of one picosecond, which is the finest granularity of the time data type. This result strengthens the confidence in a correct implementation of the communication models in simulation.

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