Statistical Delay Bound for WirelessHART Networks

In this paper we provide a performance analysis framework for wireless industrial networks by deriving a service curve and a bound on the delay violation probability. For this purpose we use the (min,x) stochastic network calculus as well as a recently presented recursive formula for an end-to-end delay bound of wireless heterogeneous networks. The derived results are mapped to WirelessHART networks used in process automation and were validated via simulations. In addition to WirelessHART, our results can be applied to any wireless network whose physical layer conforms the IEEE 802.15.4 standard, while its MAC protocol incorporates TDMA and channel hopping, like e.g. ISA100.11a or TSCH-based networks. The provided delay analysis is especially useful during the network design phase, offering further research potential towards optimal routing and power management in QoS-constrained wireless industrial networks.Comment: Accepted at PE-WASUN 201

Calculus of service guarantees for network coding

A large class of networks is able to provide some guarantees in terms of quality of service, end-to-end delays and throughput to data flows. In return, the data flows must verify constraints of burstiness and throughput. The aim of this work is to introduce and evaluate the network coding for independent flows in such networks. First, we present efficient coding nodes strategies allowing the building of output flows as a combination of a subset of all the input flows. These strategies are evaluated in terms of maximal output throughput, maximum buffer size and maximal crossing-delays of the network node. In a second part, we show that a generalization of these results to a complete network can be obtained through a transfer matrix whose entries are expressed in terms of network calculus. Thanks to the formalism used to characterize the flows, the obtained results can be considered as guarantees in terms of the burstiness, buffers size or end-to-end delays