By advancing technologies in both hardware and software, it is possible to support more complex applications. Wireless Sensor Networks (WSNs) comprised of tiny sensing devices with wireless radios are the key enablers for future Internet of Things(IoT) applications, where collecting measurements and delivering them to their destination is the most important task. In traditional sensor networks, sensor nodes were typically stationary and each node periodically measured and sent data to the next predefined router. However, in current applications, some nodes are expected to move. For instance, in health monitoring applications, where patients with sensors attached to their body are free to move in the hospital or their houses. Software Defined Networking (SDN) is a technique that was conventionally used in wired networks, and recently was used in some wireless networks, such as cellular and wireless local area networks. The idea of SDN is to provide more flexibility in the network by getting the advantage of re-programmability of the network devices during run-time. In networks based on SDN, the control plane is shifted from the infrastructure to a higher level in order to provide re-configuration. The controller decides on updating forwarding rules by getting some feedback from nodes in the network. In wireless sensor networks, the feedback may contain information related to the link quality and available resources such as battery level and the location of the sensor node (number of hops away from the sink). In this thesis, a study ofseveral relevant SDN-based architectures for wireless sensor networks is given, outlining the main advantages and disadvantages for each. In addition, some mobility solutions in sensor networks such as localization, routing and hand-off algorithms are explored. One of the drawbacks with SDN is that it was originally built for wired networks there experience with mobility does not exist. Thus the thesis considers the possibility to use SDN solutions in WSN were certain applications are in need of mobility. Finally, the thesis propose mobility solution for sensor networks that takes advantage of SDN and uses a handoff algorithm. In fact, the hand-off mechanism is achieved by means of control message exchanges that is supervised by the controller.

This report focuses on finding best practices and a better methodology when performing computer network analysis and troubleshooting. When network analysis is performed, computer network data packets are captured using data capturing software. The data packets can then be analysed through a user interface to reveal potential faults in the network. Network troubleshooting is focusing more on methodology when finding a fault in a network. The thesis work was performed at Cygate where they have recently identified needs for an updated network analysis methodology and a documentation template when documenting the network analysis results. Thus, the goal of this thesis has been to develop an elaborated methodology and discover best practices for network analysis and to write a documentation template for documenting network analysis work. As a part of discovering best practices and a methodology for network analysis, two laboratory tests were performed to gather results and analyse them. To avoid getting too many results but to still keep the tests within the scope of this thesis, the laboratory tests were limited to four network analysis tools and two test cases that are explained below. In the first laboratory test during three different test sequences, voice traffic (used in IP-phones and Skype etc.) is sent in the network using a computer program. In two of the test sequences other traffic is also congesting the network to disturb the sensitive voice traffic. The program used to send the voice traffic then outputs values; packet delay, jitter (variation in delay) and packet loss. Looking at these values, one can decide if the network is fit for carrying the sensitive voice traffic. In two of the test cases, satisfying results were gathered, but in one of them the results were very bad due to high packet loss. The second laboratory test focused more on methodology than gathering and analysing results. The goal of the laboratory test was to find and prove what was wrong with a slow network, which is a common fault in today’s networks due to several reasons. In this case, the network was slow due to large amounts of malicious traffic congesting the network; this was proven using different commands in the network devices and using different network analysis tools to find out what type of traffic was flowing in the network. The documentation template that was written as part of this thesis contains appealing visuals and explains some integral parts for presenting results when network analysis has been performed. The goal of the documentation template was an easy-to-use template that could be filled in with the necessary text under each section to simplify the documentation writing. The template contains five sections (headlines) that contain an explanation under it with what information is useful to have under that section. Cygate’s network consultants will use the documentation template when they are performing network analysis. For future work, the laboratory test cases could be expanded to include Quality of Service (QoS) as well. QoS is a widely deployed technology used in networks to prioritise different types of traffic. It could be used in the test cases to prioritise the voice traffic, in which case the results would be completely different and more favourable.

This study aims at developing curriculum for Computer and Network Engineering major which is relevant to industrial needs. The study employed the qualitative method. The data were collected through an in-depth interview, documentation, and focus group disscussion. The research population comprised of (1) industry practitioners from computer and network engineering industries, and (2) teachers of vocational high schools in Special Region of Yogyakarta. In this qualitative research, the one who became the instrument or tool of the research was the researcher himself. Understanding the qualitative research method and the knowledge related to the field of the research, the researcher was sure that he had sufficient knowledge both academically and technically. The findings of this study consisted of four parts, namely (1) standard competence of Computer and Network Engineering major for vocational high school; (2) the curriculum of Computer and Network Engineering major that is currently implemented; (3) competences in the field of Computer and Network Engineering demanded by industries; and (4) the curricuulum of Computer and Network Engineering major that is appropriate for industrial needs.

The main goal of the diploma thesis is the description of geodetic and construction activities and work processes dealing with reconstruction of the D1 highway surface in the section Rosice – Brno. The thesis is focused within the sphere of engineering geodesy and address the issue of creation of point field, stake-out, control measurement and the measurement of real building execution documents. Used survey procedures are analyzed in the context of the standard deviation listed in the project documentation or ČSN. The geotetic documentation is compiled for the chosen measured data.

<p dir="ltr">The Internet is a large network of globally interconnected devices p used to facilitate the exchange of information across different parties. As usage of the Internet is expected to grow in the future, the underlying infrastructure must be secure to ensure traffic reaches its intended destination without any disruptions. However, the primary routing protocol used on the Internet, the Border Gateway Protocol (BGP), while scalable and can properly route traffic between large networks, does not inherently have any security mechanisms built within the protocol. This leads to devices that use BGP over the internet to be susceptible to BGP Hijacking attacks, which involve maliciously injected routes into BGP’s Routing Information Base (RIB) to intentionally redirect traffic to another destination. Attempts to solve these issues in the past have been challenging due to the prevalence of devices that use BGP on the existing Internet infrastructure and the lack of backward compatibility for proposed solutions. The goal of this research is to categorize the different types of BGP Hijacking attacks that are possible on a network, identify indicators that an ongoing BGP Hijacking attack based on received routes from the Internet locally without access to machines from other locations or networks, and subsequently leverage these indicators to protect local networks from external BGP Hijacking attacks.</p>

Wireless Sensor Network (WSN) is an emerging multi-hop wireless network technology, and the greenhouse network monitoring system is one of the key applications of WSNs in which various parameters such as temperature, humidity, pressure and power can be monitored. Here, we aim to study the performance of a simulation-based greenhouse monitoring system. To design the greenhouse monitoring system based on WSN, we have used ZigBee-based devices (end devices, routers, coordinators, and actuators. Our proposed greenhouse monitoring network has been designed and simulated using the network simulator OPNET Modeller.The investigation is split into two; first, the aim is to find the optimal Transmit (Tx) power set out at sensor nodes and second, the focus is on studying how increasing the number of sensor nodes in the same greenhouse network will affect the overall network performance. ZigBee-based greenhouses corresponded to 4 network scenarios and are simulated using OPNET Modeller in which 22 different transmit (Tx) power (22 cases) in Scenario 1 is simulated, scenario 2, 3 and 4 estimated to 63, 126, 189 number of sensor nodes respectively. Investigating the performance of the greenhouse monitoring network performance metrics such as network load, throughput, packets sent/received and packets loss are considered to be evaluated under varied transmit (Tx) power and increasing number of sensor nodes. Out of the comprehensive studies concerning simulation results for 22 different transmit (Tx) power cases underlying the greenhouse monitoring network (Scenario1), it is found that packets sent/received and packets loss perform the best with the transmitted (Tx) power falling in a range of 0.9 mWatt to 1.0 mWatt while packet sent/received and packet loss are found to perform moderately with the transmitted (Tx) power values that lie in a range of 0.05 mWatt to 0.8 mWatt. Less than 0.05 mWatt and greater than 0.01 microWatt Tx power experience, the worst performance in terms of particularly packet dropped case. For instance, in the case of the packet dropped (not joined packet, i.e., generated at the application layer but not able to join the network due to lack of Tx power), with a Tx power of 0.01 mWatt, 384 packets dropped with a Tx power of 0.02 and 0.03 mWatt, 366 packets dropped, and with a Tx power of 0.04 and 0.05, 336 packet dropped.While increasing the number of sensor nodes, as in scenario 2, 3 and 4, dealing with sensor nodes 63, 126 and 189 correspondingly, the MAC load, MAC throughput, packet sent/received in scenario 2 are found to perform better than that of scenario 3 and scenario 4, while packet loss in scenarios 2, 3 and 4 appeared to be 15%, 12% and 83% correspondingly.

This thesis describes the design and deployment of netLab, a self-contained lab environment suitable for use in an upper level networking course. NetLab does not require special hardware, special permissions, kernel modifications, or multiple computers. The laboratory was designed to emphasize hands-on programming over device configuration or performance analysis. NetLab uses network engineering projects to motivate software engineering principles. The main projects are linkLab and routerLab, the implementations of a layer-2 network protocol and a layer-3 routing algorithm simulation. Both projects use a physical-layer emulator providing controllable impairment for thorough testing. The lab has been shown to be capable of expansion to accommodate different protocols. NetLab is a success in that students consistently found netLab to be challenging and exciting, and all ranks of students advanced their skills.

This thesis describes the design and deployment of netLab, a self-contained lab environment suitable for use in an upper level networking course. NetLab does not require special hardware, special permissions, kernel modifications, or multiple computers. The laboratory was designed to emphasize hands-on programming over device configuration or performance analysis. NetLab uses network engineering projects to motivate software engineering principles. The main projects are linkLab and routerLab, the implementations of a layer-2 network protocol and a layer-3 routing algorithm simulation. Both projects use a physical-layer emulator providing controllable impairment for thorough testing. The lab has been shown to be capable of expansion to accommodate different protocols. NetLab is a success in that students consistently found netLab to be challenging and exciting, and all ranks of students advanced their skills.

Thesis (MSc (Mathematical Sciences. Computer Science))--University of Stellenbosch, 2008. / Consider a path-oriented telecommunications network where calls arrive to each route in a Poisson process. Each call brings on average a fixed number of packets that are offered to route. The packet inter-arrival times and the packet lengths are exponentially distributed. Each route can queue a finite number of packets while one packet is being transmitted. Each accepted packet/call generates an amount of revenue for the route manager. At specified time instants a route manager can acquire additional capacity (“interface capacity”) in order to carry more calls and/or the manager can acquire additional buffer space in order to carry more packets, in which cases the manager earns more revenue; alternatively a route manager can earn additional revenue by selling surplus interface capacity and/or by selling surplus buffer space to other route managers that (possibly temporarily) value it more highly. We present a method for efficiently computing the buying and the selling prices of buffer space. Moreover, we propose a bandwidth reallocation scheme capable of improving the network overall rate of earning revenue at both the call level and the packet level. Our reallocation scheme combines the Erlang price [4] and our proposed buffer space price (M/M/1/K prices) to reallocate interface capacity and buffer space among routes. The proposed scheme uses local rules and decides whether or not to adjust the interface capacity and/or the buffer space. Simulation results show that the reallocation scheme achieves good performance when applied to a fictitious network of 30-nodes and 46-links based on the geography of Europe.

Multiprotocol Label Switching (MPLS) is an emerging technology which ensures the reliable delivery of the Internet services with high transmission speed and lower delays. The key feature of MPLS is its Traffic Engineering (TE), which is used for effectively managing the networks for efficient utilization of network resources. Due to lower network delay, efficient forwarding mechanism, scalability and predictable performance of the services provided by MPLS technology makes it more suitable for implementing real-time applications such as voice and video. In this thesis performance of Voice over Internet Protocol (VoIP) application is compared between MPLS network and conventional Internet Protocol (IP) network. OPNET modeler 14.5 is used to simulate the both networks and the comparison is made based on some performance metrics such as voice jitter, voice packet end-to-end delay, voice delay variation, voice packet sent and received. The simulation results are analyzed and it shows that MPLS based solution provides better performance in implementing the VoIP application. In this thesis, by using voice packet end-to-end delay performance metric an approach is made to estimate the minimum number of VoIP calls that can be maintained, in MPLS and conventional IP networks with acceptable quality. This approach can help the network operators or designers to determine the number of VoIP calls that can be maintained for a given network by imitating the real network on the OPNET simulator. / 0046737675303