The multi-net Global Routing Problem (GRP) in VLSI physical design is a problem of routing a set of nets subject to limited resources and delay constraints. Various state-of-the-art routers are available but their main focus is to optimize the wire length and minimize the over ow. However optimizing wire length do not necessarily meet timing constraints at the sink nodes. Also, in modern nano-meter scale VLSI process the consideration of process variations is a necessity for ensuring reasonable yield at the fab. In this work, we try to nd a fundamental strategy to address the timing-driven Steiner tree construction (i.e., the routing) problem subject to congestion constraints and process variation. For congestion mitigation, a gradient based concurrent approach (over all nets) of Erzin et. al., rather than the traditional (sequential) rip-and-reroute is adopted in or- der to propagate the timing/delay-driven property of the Steiner tree candidates. The existing sequential rip-up and reroute methods meet the over ow constraint locally but cannot propagate the timing constraint which is non-local in nature. We build on this approach to accommodate the variation-aware statistical delay/timing requirements. To further reduce the congestion, the cost function of the tree generation method is updated by adding history based congestion penalty to the base cost (delay). Iterative use of the timing-driven Steiner tree construction method and history based tree construction procedure generate a diverse pool of candidate Steiner trees for each net. The gradient algorithm picks one tree for each net from the pool of trees such that congestion is e ciently controlled. As the technology scales down, process variation makes process dependent param- eters like resistance, capacitance etc non-deterministic. As a result, Statistical Static Timing Analysis or SSTA has replaced the traditional static timing in nano-meter scale VLSI processes. However, this poses a challenge regarding the max/min-plus algebra of Dijkstra like approximation algorithm that builds the Steiner trees. A new approach based on distance between distributions for nding maximum/minimum at the nodes is presented in this thesis. Under this metric, the approximation algorithm for variation aware timing driven congestion constrained routing is shown to be provably tight and one order of magnitude faster than existing approaches (which are not tight) such as the MVERT. The results (mean value) of our variation aware router are quite close to the mean of the several thousand Monte Carlo simulations of the deterministic router, i.e the results converge in mean. Therefore, instead of running so many deterministic Monte Carlo simulations, we can generate an average design with a probability distribution reasonably close to that of the actual behaviour of the design by running the proposed statistical router only once and at a small fraction of the computational e ort involved in physical design in the nano regime VLSI. The above approximation algorithm is extended to local routing, especially non- Manhattan lambda routing which is increasingly being allowed by the recent VLSI tech- nology nodes. Here also, we can meet delay driven constraints better and keep related wire lengths reasonable.

This paper discsusses the question: is website oracles in Tor from timing DNS something we have to worry about? This paper builds apon the findings done by Rasmus Dahlberg and Tobias Pulls in thier paper Website Fingerprinting with Website Oracles. A website oracle is a side channel attack that answers the predicate: has this website been visited before? The website oracle is constructed and test are carried out, with great outcome, resulting in that website oracles from timing DNS is not an attack that puts individuals using Tor at risk, but certanly challanges the idea of an anonymity network when such a lot of data can be derived from DNS. / Den här uppsatsen diskuterar frågan: är ett webbplatsorakel från DNS-tidtagning i Tor en attack att oroa sig för? Uppsatsen bygger på tidigare forskning utförd av Rasmus Dahlberg och Tobias Pulls i rapporten Website Fingerprinting with Website Oracles. Ett webbplatsorakel är en sidokanalsattack som svarar på predikatet: är denna webbsida besökt av en specifik delmängd användare? Tor är ett anonymitetsnätverk för gemene man, en viktig teknik för ett utvecklande samhälle där den enskilde individens rätt över sin egen information på internet är under konstant hot. I uppsatsen förklaras vad ett webbplatsorakel är i detalj, hur webbplatsorakel fungerar i Tor-nätverket och hur detta konstrueras i detalj. Resultat presenteras och en diskussion förs med anknytning till dagens teknik och samhälle i stort. Resultaten tyder inte på någon större risk för enskilda användare av Tor men visar på en riskfylld utveckling av perceptionen av hur Tor uppfattas och hur dess rykte kan skadas om attacker likt den presenterad i uppsatsen kan vidareutvecklas. / <p>Presentation utfördes online p.g.a. coronapandemi.</p>

his semestral´s thesis deals with proposal and system implementation for automatic configuration of Cisco network devices. This system is called AutoConf and it is intended for distant copying configuration files from eagle-server to the switches and routers in Cisco academy laboratory. It is handled by web pages placed on eagle-server. In this system, user can create new laboratory exercises with configuration files for network devices and then these files could be used for configurations. Informations about done configurations are saved in relation database MySQL. Network devices which will be configured by system AutoConf have to be connected with eagle-server. To setup their connection settings was created decision-making mechanism. If it detects physical connection between network device and eagle-server before network device starts, it will set network device for communication with eagle-server.

This thesis is dedicated to the automation of tests of the thermostats developed by the company Honeywell. The first chapter presents a problem of self-testing of thermostats, followed by a discussion of possible approaches to solutions. Attention is paid to testing the functionality of the HMI of thermostats, especially to the part of the system, that deals with activation of touchscteen, but no other part of the problem are omitted in the text. Discussions of the problematic passes into the design and implementation of specific design solutions. The selected design of 3D-router, which moves in three orthogonal coordinates and resembles to a coordinate drill for example. First, it describes the basic concepts of mechanic and electronic part of equipment, and subsequently is designed and implemented control electronics for mechanical activator HMI. Each of the electronics components are described in detail and values of parts are based on the calculation with the exception of finished parts. The proposal of the electronics follows the possibility of maximization of universality module for applications in similar applications. The functionality of the electronics is controlled by a microprocessor with a custom program that is described in the work. Source code of some the programs is not available because it is know-how of the company. Next part of the thesis deals with optimization of the moving of axes, optimization is done empirically by measuring. An important issue is compliance with the accuracy required position, also part of the work is devoted to the issue of calibration position. Finally is solved the continuity on the superior system. It is designed and implemented the upper layer of the communication protocol used in the company. Work is the solution of specific corporate award thesis. Although it is a very specific role of the works are generally applicable for other applications. In particular, the proposed electronic represents relatively universal controller for stepper motor control.

Diploma thesis deals with creating four laboratory tasks using simulation tool OMNeT++ and Inet Framework extension. Subject matter of these designed tasks is focused on routing protocols, providing quality of service, computer networking technologies used in local area networks and comparison of active networking devices. First task contains the comparison of behaviour and routing techniques between protocols RIPv2 and OSPFv2, including the effect of dividing OSPF network into smaller areas. Second task is focused on various techniques for controlling quality of service, namely FIFO queue, PQ and WFQ. Main goal is the comparison of results, that define quality of network services. Third task compares networking technologies, Ethernet and WLAN, parameters of transmission. Fourth task offers comparison of networking devices, hub, switch and router. This paper also contains required theory of network technologies and software tools used for executing simulations.

This master's thesis deals with the possibilities how to guarantee the quality of service in the area of computer networks using a GNU/Linux operating system. This work compares and evaluates tools which are necessary to guarantee the quality of service. The goal of this work is to discuss the advantages and disadvantages of these tools and to design a system which handles the problem of quality of service. Designed system uses a heuristics, which allows the user to set up the quality of service system without studying specific properties of communication protocols on the network or application layer. This work also includes a theoretical introduction into the quality of service and computer networks.

An attempt to save the city of Detroit, Michigan, and its existing buildings by giving it a new meaning and future. Cars and roads are eliminated. Tiger Stadium is converted into a city-wide freight receiving and shipping facility. A system of pneumatic tubes is implemented in each neighborhood, with a district tube router facility inside the LaFayette Tower. Apartments vitalize the landmark Fisher Building. A new multi-storey research/ education/ work station with more stairs then elevators fills in an old parking lot. / Master of Architecture

This thesis discuss about the problem with mobility of stations in IP networks, concretely protocol Mobile IP and about the problems with this protocol in MANET networks, with the scope on Motorola MESH. First part is about design integration of protocol Mobile IP in this networks with usage Tropos 5210 MetroMesh routers and Cisco components (router, switch) to design and configure wireless MESH network, than connect this network with Cisco components and try to implement Mobile IP into this network. Second part is about design and configure wireless network from Cisco Wireless Access Points and about succesfully implementation of Mobile IP protocol into this network. In the last part is some tests of the function and quality of this topology.

Asynchronous multiplexing schemes are efficient than synchronous schemes, in a bursty traffic environment of multiple access local area network (LAN), as fixed bandwidth is not allocated among the users and there is no access delay. Fiber- Optic Code-Division Multiple Access (FO-CDMA) is one such asynchronous multiplexing scheme suitable for high speed LAN networks. While FO-CDMA offers potential benefits it also faces challenges in three diverse areas which are 1) coding algorithms and schemes 2) advanced encoding and decoding hardware and 3) network architecture. In this thesis, as a solution to the first challenge, we propose the design and construction of a new family of codes, wavelength/time multiple-pulses-per-row (W/T MPR) codes. These codes have good cardinality, spectral efficiency and minimal cross-correlation values. Performance analysis of the W/T MPR codes is carried out and found to be superior to other codes. In unipolar 1-D Optical Orthogonal Codes (OOCs) proposed by Salehi et al., the ratio of code length/code weight grows rapidly as the number of users is increased for a reasonable weight. Hence, for a given pulse width, the data rate decreases or in other words for a given data rate very narrow pulses have to be used, because of which dispersion effects will be dominant. To overcome the drawbacks of non-linear effects in large spread sequences of 1-D unipolar codes in FO-CDMA networks, several two-dimensional codes have been proposed. Wavelength-time (W/T) encoding of the two-dimensional codes is practical in FO-CDMA networks. W/T codes reported so far can be classified mainly into two types: 1) hybrid sequences, where one type of sequence is crossed with another to improve the cardinality and correlation properties and 2) matrix codes, 1-D sequences converted to 2-D codes or 2-D codes by construc- tion, to reduce the ’time’ spread of the sequences/codes. Prime-hop and eqc/prime W/T hybrid codes have been proposed where one type of sequence is crossed with another to improve the cardinality and correlation properties. Other constructions deal with conversion of 1-D sequences to 2-D codes either by using Chinese remainder theorem or folding GoLomb rulers. W/T single-pulse-per-row (W/T SPR) codes are 2-D codes constructed using algebraic method Addition Modulo Group operation. Motivation for this work: To design a family of 2-D codes which have the design choice of length of one dimension over the other, and also have better cardinality, spectral efficiency and also low cross-correlation values (thereby have low BER) than that of the reported unipolar 2-D codes. In this thesis, we describe the design principles of W/T MPR codes, for in- coherent FO-CDMA networks, which have good cardinality, spectral efficiency and minimal cross-correlation values. Another feature of the W/T MPR codes is that the aspect ratio can be varied by trade off between wavelength and temporal lengths. We lay down the necessary conditions to be satisfied by W/T MPR codes to have minimal correlation values of unity. We analytically prove the correlation results and also verify by simulation (of the codes) using Matlab software tool. We also discuss the physical implementation of the W/T MPR FO-CDMA network with optical encoding and decoding. We show analytically that when distinct 1-D OOCs of a family are used as the row vectors of a W/T MPR code, it will have off-peak autocorrelation equal to ‘1’. An expression for the upper bound on the cardinality of W/T MPR codes is derived. We also show that 1-D OOCs and W/T SPR codes are the limiting cases of W/T MPR codes. Starting with distinct 1-D OOCs, of a family, as row vectors, we propose a greedy algorithm, for the construction of W/T MPR codes and present the repre- sentations of the results. An entire W/T MPR code family, generated using greedy algorithm, is simulated for various number of interfering users. Performance analysis of the W/T MPR codes and their limiting cases is carried out for various parameter variations such as the dimensions of wavelength, time and weight of the code. We evaluate the performance in terms of BER, capacities of the networks, temporal lengths needed (to achieve a given BER). Multiple access interference (MAI) signal can be reduced, by using a bistable optical hard-limiter device in the W/T MPR code receiver, by eliminating those signal levels which exceed a certain preset level. Performance analysis of the W/T MPR codes and their limiting cases is studied for various parameter variations. For given wavelength × time dimensions, we compare various W/T codes, whose cardinalities are known, and show that W/T MPR family of codes have better cardinality and spectral efficiency than the other (reported) W/T codes. As W/T MPR codes are superior to other W/T codes in terms of cardinality, spectral efficiency, low peak cross-correlation values and at the same time have good performance, makes it a suitable coding scheme for incoherent FO-CDMA access networks.

Computing with mobile agents is rapidly becoming a topic of mainstream research in the theory of distributed computing. The main research questions undertaken in this study concern the feasibility of solving fundamental tasks in an anonymous network, subject to limitations on the resources available to the agent. The considered challenges include: exploring a graph by means of an agent with limited memory, discovery of the network topology, and attempting to meet with another agent in another network (rendezvous). The constraints imposed on the agent include the number of moves which the agent is allowed to perform in the network, the amount of state memory available to the agent, the ability of the agent to communicate with other agents, as well as its a priori knowledge of the network topology or of global parameters.