This thesis was about investigating if it is feasible to implement an IP-forwarding data plane on a GPU. A GPU is energy efficient compared to other more powerful processors on the market today and should in theory be efficient to use for routing purposes. An IP-forwarding data plane consist of several things where we focused on some of the concepts. We have implemented IP-forwarding lookup operations, packet header changes, prioritization between different packets and a traffic shaper to restrict the packet throughput. To test these concepts we implemented a prototype, on a Tegra platform, in CUDA and evaluated its performance. We are able to forward 28 Mpackets/second with a best case latency of 27 µS given local simulated packets. The conclusions we can draw of this thesis work is that using a GPU for IP-forwarding purposes seems like an energy efficient solution compared to other routers on the market today. In the thesis we also tried the concept of only launching the GPU kernel once and let it be infinite which shows promising results for future work.

This thesis is split into two parts: first a statistical analysis of multi-hop MIMO relay networks, followed by a simulation of the perfomance of a P25 SISO multi-hop relay network. The basis of the MIMO section is the developement of an end to end statistical model of the multiple relay channel. This end to end model simplifies the statistics involved, making the analysis of systems with large numbers of relays and antennas more practical. A partial system model is obtained. This is exact for a multiple input single output network and can be used to describe the received signal at a single antenna in a multiple output system. We go on to look at the relationship between end to end system parameters and the paramters of individual inter-relay channels. The SISO section contains a characterisation of BER for P25 relay chains. The effect of the SNR at each relay node, the nature of the channel and the number of relay hops on the BER is determined. Furthermore, the performance trends are compared for a range of common relaying protocols, including amplify and forward and two types of decode and forward.

The current Internet routing and addressing architecture is facing a serious scalability problem. The default free zone (DFZ) routing table size grows at an increasing and potentially alarming rate. The Internet architecture uses a single namespace - the IP address, to express two functions about a network entity: its identifier and locator. This overloading of semantics leads to the scalability problem as a consequence of multihoming, traffic engineering, and nonaggregatable address allocations. The current Internet architecture does not inherently support emerging features such as mobility either. This thesis presents a simple addressing and forwarding architecture (SAFA) for the Internet. SAFA separates the locator namespace from the ID namespace so that the locators can follow the hierarchies in the Internet topology and be aggregated. The locators are allocated dynamically and automatically. The hierarchical format of locators gives end systems more control over the route selection. A straightforward forwarding scheme is designed based on the hierarchical addressing scheme. The meshed part of the Internet topology is integrated into the forwarding procedure through a special forwarding table. With a rendezvous service that maps from IDs to locators, SAFA also provides scalable support for mobility, multihoming and traffic engineering. Our work also includes an Internet topology study and a prototype implementation of the architecture. The evaluation results suggest that SAFA would be feasible in the current Internet if deployed.

The current Internet routing and addressing architecture is facing a serious scalability problem. The default free zone (DFZ) routing table size grows at an increasing and potentially alarming rate. The Internet architecture uses a single namespace - the IP address, to express two functions about a network entity: its identifier and locator. This overloading of semantics leads to the scalability problem as a consequence of multihoming, traffic engineering, and nonaggregatable address allocations. The current Internet architecture does not inherently support emerging features such as mobility either. This thesis presents a simple addressing and forwarding architecture (SAFA) for the Internet. SAFA separates the locator namespace from the ID namespace so that the locators can follow the hierarchies in the Internet topology and be aggregated. The locators are allocated dynamically and automatically. The hierarchical format of locators gives end systems more control over the route selection. A straightforward forwarding scheme is designed based on the hierarchical addressing scheme. The meshed part of the Internet topology is integrated into the forwarding procedure through a special forwarding table. With a rendezvous service that maps from IDs to locators, SAFA also provides scalable support for mobility, multihoming and traffic engineering. Our work also includes an Internet topology study and a prototype implementation of the architecture. The evaluation results suggest that SAFA would be feasible in the current Internet if deployed.

We propose a new architecture for wireless mesh networks. In addition to forwarding packets, routers mix (i.e., code) packets from different sources to increase the information content of each transmission. We show that intelligently mixing packets increases network throughput. Our design is rooted in the theory of network coding. In contrast to prior work on network coding, which is mainly theoretical and focuses on multicast traffic, ours is practical and solves the common case of unicast traffic. We present the first implementation of network coding in a wireless network. Our system introduces a coding layer between the IP and MAC layers. It works with UDP and TCP traffic, and hence seamlessly integrates with existing applications. We evaluate our design on a 34-node wireless testbed and show that it delivers a 3-4x increase in the throughput ofwireless mesh networks.

The first part of the thesis contains brief characteristic of the company, analasis of logistic services, level of services offered and logistic costs. The synthetic part of the thesis uses the knowledge from the analytical part to reach the goal of the thesis. Attention is also given to the evaluation of applied methods of collecting data. Methods used in the thesis are mostly observing, specifically the shot of a working day and measuring. The next method which is applied is a survey. The output of the synthetic part is an improvement proposal to existing processes, then suggestions for the future orientation in the area of communication technology, more specifically using the ECOM applications. In the synthetic part, there was used a mathematical model called travelling salesman problem to evaluate the optimality of courier routes.

The goal of this thesis is to analyze the forwarding and courier services at selected subjects. In this thesis I analyze and compare a total of eight transportation companies. These are: Czech Post, DHL Express s.r.o., PPL CZ s.r.o., TNT Express Worldwide, s.r.o., DPD CZ s.r.o., Czech Republic Dachser, a.s., ČSAD Jihotrans, a.s.., Spedica,s.r.o. Other goal of this thesis is to determine whether there are too many similar companies in the market, and whether there is still space for new forwarding company.

Main goal of my dissertation is to refer to basic accounting and economic problems in logistics. Theoretical part is focused on main decision problems in the beginning of enterprise activities (convenience of acquisition warehouse building or its lease, comparison transportation by own vehicles with lease of transportation duty, specification of standards required characters of accounting and infomation system). In a dissertation im focusing also on accounts payable remittance and well timed servicing the debts. The end of my dissertation is presented to exchange rate differences. In a practical part im applying theoretical knowledges to a concrete logistics company and im assessing its activities.

In all harvesting operations, minimized risks for soil damage combined with short forwarding mileage are desirable in order to achive cost efficient work. This study examined how forwarding mileage are influenced by the time of the year a harvesting operation is conducted. Two scenarios that corresponded to the terrain water conditions during wet and drier periods of the year were created. Twenty harvesting sites were simulated with these scenarios. The results showed that the forwarder’s mileage was reduced in the dry conditions, and that even the forwarder’s mileage over wet areas was reduced under these conditions. This means that there is a potential for productivity increase as well as to reduce the risk of soil damage in wet areas.

The internet data traffic is tripling every two years due to the exponential growth in the number of routers. Routers implement the packet classification methodology by determining the flow of the packet, based on various rule checking mechanisms that are performed on the packet headers. However, the memory components like TCAMs used by these various rules are very expensive and power hungry. Henceforth, the current IP Lookup algorithms implemented in hardware are even though able to achieve multi-gigabit speeds, yet suffer with great memory overhead. To overcome this limitation, we propose a packet classification methodology that comprises of MicroCuckoo-hash technique, to route packets. This approach alleviates the memory requirements significantly, by completely eliminating the need for TCAM cells. Cuckoo hash is used to achieve very high speed, hardware accelerated table lookups and also are economical compared to TCAMs. The proposed IP Lookup algorithm is implemented as a simulation-based hardware/software model. This model is developed, tested and synthesized using Vivado HLS tool. / Master of Science