The analysis of network traffic can provide important information for network operators and administrators. One of the main purposes of traffic analysis is to identify the traffic mixture the network carries. A couple of different approaches have been proposed in the literature, but none of them performs well for all different application traffic types present in the Internet. Thus, a combined method that includes the advantages of different approaches is needed, in order to provide a high level of classification completeness and accuracy. According to our best knowledge, this study is the first attempt where the currently known traffic classification methods are benchmarked on network traces captured in operational mobile networks. The pros and cons of the classification methods are analyzed, based on the experienced accuracy for different types of applications. Using the gained knowledge about the strengths and weaknesses of the existing approaches, a novel traffic classification method is proposed. The novel method is based on a complex decision mechanism, in order to provide an appropriate identification mode for each different application type. As a consequence, the ratio of the unclassified traffic becomes significantly lower. Further, the reliability of the classification improves, as the various methods validate the results of each other. The novel method is tested on several network traces, and it is shown that the proposed solution improves both the completeness and the accuracy of the traffic classification, when compared to existing methods.

The hose resource provisioning model promises to provide an easy-to-use characterization framework for virtual private network service offerings. Significant research effort has recently been spent on proposing new algorithms for provisioning cost-optimal networks specified according to this new model. However, a detailed comparison of the bandwidth requirement for networks designed based on the hose model and networks designed based on the traditional pipe model has not been performed. The first contribution of this paper is a detailed comparison of the bandwidth needs of the two models assuming a range of network sizes and network topologies. This numerical evaluation required efficient calculation methods for determining resource allocation based on the hose model parameters, therefore, a linear programming based formulation is also presented for this purpose. The second contribution is the calculation of a lower bound for the hose based realization. This lower bound is very useful in evaluating the two models given that the problem of provisioning a minimal cost network based on the hose model specification can only approximately be solved in polynomial time.

ATM AAL2 has been selected as the transmission technology in the radio access network of UMTS systems. To suit AAL2 to a network where support for soft handoff is essential, an additional switching level on top of ATM has been developed. AAL2 signalling is a new protocol which is capable of handling on-demand, switched AAL2 connections. For supporting soft handoff, the most important requirement is fast connection setup. A generic model for an AAL2 switch is presented, and a new method is proposed for optimising the distribution of processor resources between the functional entities of the switch in order to achieve the fastest possible connection setup time. Then AAL2 switching networks, resembling the UMTS terrestrial radio access network, are built using an optimised AAL2 switch model, and the performance of the AAL2 signalling protocol is evaluated by simulation. It is shown that further reduction of the connection setup time can be achieved by introducing priority queueing of AAL2 signalling messages.