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SUMMARYMultipath routes in wireless multihop ad hoc networks have proven to increase performance compared to single path routing when providing backup paths in case of path failures and also distributing flows (i.e. data traffic) among several paths. The drawback of using multipath simultaneously in wireless multihop ad hoc networks is that the other nodes in the network located in the other active paths may interfere with their own communications, degrading the effective throughput. This work proposes an analytical model to find multiple non-interfering routes or routes with minimum interference between a source and a destination in a given network topology. These types of routing paths are called Radio Disjoint Multipath (RDM) routes. Compared to the previous work, this work pioneers the use of models to determine interference free routes in a wireless multihop ad hoc network considering two criteria: the mutual interference of each path and the background traffic load of the path. Further, simulation results are taken by implementing RDM routes in 802.11 based multihop ad hoc networks. Both analytical and simulation results are obtained and analysed for different network scenarios that use RDM routes by distributing packets of a single flow among multiple RDM paths. Analytical results show that the sustainable throughput can be doubled when using RDM paths for unidirectional flows. Simulation results also show that throughput can be improved with RDM routes by a factor of 1.5 and 1.8 in some cases, when using uniand bidirectional UDP flows, respectively.

Abstract. Fire fighters often work in dangerous and dynamic environments, which results in frequent change of network topologies and routing requirements. While the existing routing protocols are not able to cope with such a changeable environment, this paper proposes a self adaptive hybrid routing algorithm. This routing algorithm can switch between the proactive routing algorithm and reactive routing algorithm for each node pair automatically. An analytical model is created to describe the routing switch decision making algorithm. This model is based on a set of the cost functions. A numerical example shows the necessity of switching routing algorithms to reduce the overall control message overhead.

This paper presents dimensioning of an IP-based UMTS Terrestrial Radio Access Network (UTRAN) with multiple Node Bs connected to one RNC, where the applied QoS architecture is based on Differentiated Service (DiffServ) with an integrated Weighted Fair Queue (WFQ) and Strict Priority (SP) scheduling. To provide an appropriate network dimensioning for guaranteeing a desired end-to-end QoS, a general analytical approach is proposed in this paper to dimension the individual links of the Iub interface (between the Node B and the RNC) and furthermore to derive overbooking for the backbone link for elastic traffic. The analytical approach is validated by simulations. Furthermore, based on the proposed analytical approach, important dimensioning rules are summarized.