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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Detecting changes in UERC switches : A sequence analysis of UERC switches in  a mobile network

Olofsson, Lars-Gunnar, Hellman, Jacob January 2014 (has links)
This thesis investigates the possibility to analyse a mobile network with sequences of UERC switches specific to each user equipment. An UERC is essentially a channel that carries information and a user equipment connects to different UERCs depending on whether they want to talk and/or send data with different qualities. As a major player in the mobile technology industry, Ericsson strives to optimise the use of the UERCs and are looking for an automated way to detect changes. The first task was to identify and retrieve the required events from the network log files in order to create the UERC sequences. As a way to test the thesis assumption, and give a proof of concept, two different data sets were analysed were changes had been made to the network settings that should have affected the UERC sequences. With the use of n-grams, Markov chains and Bayesian Estimation testing, the changes could be identified and the thesis assumption could be confirmed - UERC sequences provides a possible way of analysing a mobile network.
2

Anonymity Protection and Access Control in Mobile Network Environment

January 2016 (has links)
abstract: Wireless communication technologies have been playing an important role in modern society. Due to its inherent mobility property, wireless networks are more vulnerable to passive attacks than traditional wired networks. Anonymity, as an important issue in mobile network environment, serves as the first topic that leads to all the research work presented in this manuscript. Specifically, anonymity issue in Mobile Ad hoc Networks (MANETs) is discussed with details as the first section of research. To thoroughly study on this topic, the presented work approaches it from an attacker's perspective. Under a perfect scenario, all the traffic in a targeted MANET exhibits the communication relations to a passive attacker. However, localization errors pose a significant influence on the accuracy of the derived communication patterns. To handle such issue, a new scheme is proposed to generate super nodes, which represent the activities of user groups in the target MANET. This scheme also helps reduce the scale of monitoring work by grouping users based on their behaviors. The first part of work on anonymity in MANET leads to the thought on its major cause. The link-based communication pattern is a key contributor to the success of the traffic analysis attack. A natural way to circumvent such issue is to use link-less approaches. Information Centric Networking (ICN) is a typical instance of such kind. Its communication pattern is able to overcome the anonymity issue with MANET. However, it also comes with its own shortcomings. One of them is access control enforcement. To tackle this issue, a new naming scheme for contents transmitted in ICN networks is presented. This scheme is based on a new Attribute-Based Encryption (ABE) algorithm. It enforces access control in ICN with minimum requirements on additional network components. Following the research work on ABE, an important function, delegation, exhibits a potential security issue. In traditional ABE schemes, Ciphertext-Policy ABE (CP-ABE), a user is able to generate a subset of authentic attribute key components for other users using delegation function. This capability is not monitored or controlled by the trusted third party (TTP) in the cryptosystem. A direct threat caused from this issue is that any user may intentionally or unintentionally lower the standards for attribute assignments. Unauthorized users/attackers may be able to obtain their desired attributes through a delegation party instead of directly from the TTP. As the third part of work presented in this manuscript, a three-level delegation restriction architecture is proposed. Furthermore, a delegation restriction scheme following this architecture is also presented. This scheme allows the TTP to have full control on the delegation function of all its direct users. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2016
3

AN EVALUATION OF TERRESTRIAL WIRELESS NETWORK MODELING APPROACHES FOR THE SPACE MOBILE NETWORK

Newton, Todd A., Roberts, Christopher J., Fletcher, Gregory G., Rossiter, Daniel S. 10 1900 (has links)
The Space Mobile Network (SMN) is NASA’s next generation architecture concept for communications services between ground and space-based assets. The SMN calls for a paradigm shift in space communications. The transition will move from an approach based on static, preplanned communications over point-to-point channels to a dynamic, event-driven, and network-based approach that facilitates service-oriented communications. In doing so, the SMN is able to leverage some concepts and technologies present in today’s terrestrial wireless networks, while others must be extended or adapted to the space communications domain. This paper provides background on key SMN architectural concepts and an evaluation of the suitability of terrestrial wireless network modeling tools to be used and applied for proving out SMN concepts.
4

Investigating the relationship between mobile network performance metrics and customer satisfaction

Labuschagne, Louwrens 16 March 2020 (has links)
Fixed and mobile communication service providers (CSPs) are facing fierce competition among each other. In a globally saturated market, the primary di↵erentiator between CSPs has become customer satisfaction, typically measured by the Net Promoter Score (NPS) for a subscriber. The NPS is the answer to the question: ”How likely is it that you will recommend this product/company to a friend or colleague?” The responses range from 0 representing not at all likely to 10 representing extremely likely. In this thesis, we aim to identify which, if any, network performance metrics contribute to subscriber satisfaction. In particular, we investigate the relationship between the NPS survey results and 11 network performance metrics of the respondents of a major mobile operator in South Africa. We identify the most influential performance metrics by fitting both linear and non-linear statistical models to the February 2018 survey dataset and test the models on the June 2018 dataset. We find that metrics such as Call Drop Rate, Call Setup Failure Rate, Call Duration and Server Setup Latency are consistently selected as significant features in models of NPS prediction. Nevertheless we find that all the tested statistical and machine learning models, whether linear or non-linear, are poor predictors of NPS scores in a month, when only the network performance metrics in the same month are provided. This suggests that either NPS is driven primarily by other factors (such as customer service interactions at branches and contact centres) or are determined by historical network performance over multiple months.
5

Návrh metodiky pro výběr provozovatelů virtuálního operátora v ČR / Design of metodology for selection of virtual network operators in Czech republic

Opatřil, Marek January 2012 (has links)
The main aim of this work is design methodology for the selection of subject - service provider of virtual operator in the Czech Republic and applied methodology on several subjects. Another aim is to analyze the situation in the mobile telecommunications markets in the world, especially from the perspective of MVNO. The last objective is a detailed characterization of conditions and the state of the mobile telecommunications market in the Czech Republic The second chapter describes the entities of mobile telecommunications market with a detailed focus on MVNO. The third chapter describes the critical factors that determine success MVNO. Later in thesis I analyze the mobile virtual network operator in the world and focuses on the Czech telecommunications market. In the final phase of thesis is I design methodology for selecting potential operator - the operator a virtual mobile operator in the Czech Republic, along with the application of the methodology on several subjects and verification. The benefit of this work is proposed methodology and its application for companies that are interested in entering the Czech telecommunications market through mobile virtual operator and companies that offer foundation and the know-how to potential operators of mobile virtual network operator. A side benefit of this work is a comprehensive look at the principle of operation of mobile virtual network operators in telecommunications.
6

Network Exceptions Modelling Using Hidden Markov Model : A Case Study of Ericsson’s DroppedCall Data

Li, Shikun January 2014 (has links)
In telecommunication, the series of mobile network exceptions is a processwhich exhibits surges and bursts. The bursty part is usually caused by systemmalfunction. Additionally, the mobile network exceptions are often timedependent. A model that successfully captures these aspects will make troubleshootingmuch easier for system engineers. The Hidden Markov Model(HMM) is a good candidate as it provides a mechanism to capture both thetime dependency and the random occurrence of bursts. This thesis focuses onan application of the HMM to mobile network exceptions, with a case study ofEricsson’s Dropped Call data. For estimation purposes, two methods of maximumlikelihood estimation for HMM, namely, EM algorithm and stochasticEM algorithm, are used.
7

Product & Pricing Standardization within the Global Mobile Network Operator Industry

Laws, Richard, Mo, Ni January 2015 (has links)
Aim: This study focuses on the degree to which mobile network operators standardize or adapt their product and pricing strategies amongst their foreign subsidiaries. Method: 10 mobile network operators with large overseas business investments and 70 of their foreign majority-owned subsidiaries are included in this empirical analysis. Variables related to data, SMS, Voice, and other relevant variables, are selected to represent ‘product’ marketing characteristics; and number of plans and specific price points across three ‘price baskets’ to represent ‘price’ marketing. Results & Conclusion: MNOs exhibited a moderate degree of standardization in terms of product design, with a lesser degree of standardization for price. Standardization scores were highly positively correlated to subsidiary operations in markets within the same region and level of economic development as the domestic market. There is also a notable clustering of marketing approaches in the Sub-Saharan African region. Implications: Existing research on standardization is reinforced by these results. Future research on the MNO industry, if global in nature, will need to account for the large degree of differences between markets. If focused on specific regions, studies can proceed on the basis of similarity in marketing strategies. Contribution: This is the most recent quantitative study on standardization in the MNO industry carried out in the last 10 years. Since that time the industry has also undergone significant changes.
8

Secure Software and Communication on Handheld Devices / Säker programvara och kommunikation med handdatorer

Hussain, Musharrif, Mahmood, Sulman January 2007 (has links)
Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system. / Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system. / +46 762733374 +46 737038932
9

Hodnocení efektivity prodejní sítě telekomunikačního operátora za použití modelů analýzy obalu dat / Using Data Envelopment Analysis models to assess efficiency of shop network of a Mobile Network Operator

Šabata, Ondřej January 2009 (has links)
This master thesis deals with efficiency assessment of shop network of a leading Mobile Network Operator, by which it utilizes an innovative approach called Data Envelopment Analysis (DEA). The following three areas are in main focus of this thesis: advantages of DEA modelling compared to common approaches to Decision Making Units efficiency assessment and extensive summary of majority of DEA models, which are relevant for solving the given problem; followed by a comprehensive model of efficiency assessment of shop network of a Mobile Network Operator, which is unique to this thesis from both theoretical and practical standpoints; and last but not least a detailed analysis of the shop network including recommendations.
10

Mobilní komunikace v ČR / Mobile Communications in the Czech Republic

Diblík, Jaroslav January 2013 (has links)
The thesis deals with the topic of mobile communication in Czech republic. Its main task is to make reader fimiliar with different types of technology and digital standards on Czech mobile communication market. Thesis shows mobile communication providers in Czech republic, not only the conventional ones, but especially virtual operators(MVNO). It defines the legislation and position of Czech Telecommunication Office (ČTÚ). At the end, it analyzes the current market situation and try to offer the best solution for possible customer and also tries to find out whether it would pay off to the customer to switch to the virtual operator, based on mobile tariff price calculator.

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