The Bluetooth Scatternet Formation (BSF) problem can be defined as the problem of forming wireless networks of Bluetooth devices in an efficient manner. A number of restrictions imposed by the Bluetooth specifications make the BSF problem challenging and unique. Many interesting solution algorithms have been proposed in the literature to solve this problem. In this thesis, we investigate the BSF problem. We concentrate on problems introduced by the procedures of device discovery of the Bluetooth specifications and on the different solutions used by BSF algorithms to deal with these problems. We study also in this thesis problems introduced by the specifications of link establishment in Bluetooth due to their close interaction with the device discovery specifications. We survey and categorize the different device discovery techniques used by BSF algorithms. This categorization is then used as a basis to identify the different theoretical computational models used to study BSF algorithms. We argue, in this thesis, that the currently available models for Bluetooth wireless networks do not model adequately, in most cases, the complexities of the Bluetooth specifications and we show that these models were oversimplified in many cases. A general computational model will be useful as a starting point to design BSF algorithms and to compare the different and numerous BSF algorithms – especially in term of the execution time efficiency. In this thesis, we provide a set of suggestions that will help in the creation of such model. We survey a number of studies that examined in more depth the specifications of device discovery in Bluetooth. We survey also other studies that attempted to simplify the Bluetooth network model, either by suggesting modifications on the Bluetooth specifications or by the use of communication technologies other than Bluetooth. Finally, we present some experiments accompanied with analyzes to show the complexities of the Bluetooth specifications and their sensitivity to minor changes (whether in the specifications or in their implementation).

The Bluetooth Scatternet Formation (BSF) problem can be defined as the problem of forming wireless networks of Bluetooth devices in an efficient manner. A number of restrictions imposed by the Bluetooth specifications make the BSF problem challenging and unique. Many interesting solution algorithms have been proposed in the literature to solve this problem. In this thesis, we investigate the BSF problem. We concentrate on problems introduced by the procedures of device discovery of the Bluetooth specifications and on the different solutions used by BSF algorithms to deal with these problems. We study also in this thesis problems introduced by the specifications of link establishment in Bluetooth due to their close interaction with the device discovery specifications. We survey and categorize the different device discovery techniques used by BSF algorithms. This categorization is then used as a basis to identify the different theoretical computational models used to study BSF algorithms. We argue, in this thesis, that the currently available models for Bluetooth wireless networks do not model adequately, in most cases, the complexities of the Bluetooth specifications and we show that these models were oversimplified in many cases. A general computational model will be useful as a starting point to design BSF algorithms and to compare the different and numerous BSF algorithms – especially in term of the execution time efficiency. In this thesis, we provide a set of suggestions that will help in the creation of such model. We survey a number of studies that examined in more depth the specifications of device discovery in Bluetooth. We survey also other studies that attempted to simplify the Bluetooth network model, either by suggesting modifications on the Bluetooth specifications or by the use of communication technologies other than Bluetooth. Finally, we present some experiments accompanied with analyzes to show the complexities of the Bluetooth specifications and their sensitivity to minor changes (whether in the specifications or in their implementation).

The Bluetooth Scatternet Formation (BSF) problem can be defined as the problem of forming wireless networks of Bluetooth devices in an efficient manner. A number of restrictions imposed by the Bluetooth specifications make the BSF problem challenging and unique. Many interesting solution algorithms have been proposed in the literature to solve this problem. In this thesis, we investigate the BSF problem. We concentrate on problems introduced by the procedures of device discovery of the Bluetooth specifications and on the different solutions used by BSF algorithms to deal with these problems. We study also in this thesis problems introduced by the specifications of link establishment in Bluetooth due to their close interaction with the device discovery specifications. We survey and categorize the different device discovery techniques used by BSF algorithms. This categorization is then used as a basis to identify the different theoretical computational models used to study BSF algorithms. We argue, in this thesis, that the currently available models for Bluetooth wireless networks do not model adequately, in most cases, the complexities of the Bluetooth specifications and we show that these models were oversimplified in many cases. A general computational model will be useful as a starting point to design BSF algorithms and to compare the different and numerous BSF algorithms – especially in term of the execution time efficiency. In this thesis, we provide a set of suggestions that will help in the creation of such model. We survey a number of studies that examined in more depth the specifications of device discovery in Bluetooth. We survey also other studies that attempted to simplify the Bluetooth network model, either by suggesting modifications on the Bluetooth specifications or by the use of communication technologies other than Bluetooth. Finally, we present some experiments accompanied with analyzes to show the complexities of the Bluetooth specifications and their sensitivity to minor changes (whether in the specifications or in their implementation).

The Bluetooth Scatternet Formation (BSF) problem can be defined as the problem of forming wireless networks of Bluetooth devices in an efficient manner. A number of restrictions imposed by the Bluetooth specifications make the BSF problem challenging and unique. Many interesting solution algorithms have been proposed in the literature to solve this problem. In this thesis, we investigate the BSF problem. We concentrate on problems introduced by the procedures of device discovery of the Bluetooth specifications and on the different solutions used by BSF algorithms to deal with these problems. We study also in this thesis problems introduced by the specifications of link establishment in Bluetooth due to their close interaction with the device discovery specifications. We survey and categorize the different device discovery techniques used by BSF algorithms. This categorization is then used as a basis to identify the different theoretical computational models used to study BSF algorithms. We argue, in this thesis, that the currently available models for Bluetooth wireless networks do not model adequately, in most cases, the complexities of the Bluetooth specifications and we show that these models were oversimplified in many cases. A general computational model will be useful as a starting point to design BSF algorithms and to compare the different and numerous BSF algorithms – especially in term of the execution time efficiency. In this thesis, we provide a set of suggestions that will help in the creation of such model. We survey a number of studies that examined in more depth the specifications of device discovery in Bluetooth. We survey also other studies that attempted to simplify the Bluetooth network model, either by suggesting modifications on the Bluetooth specifications or by the use of communication technologies other than Bluetooth. Finally, we present some experiments accompanied with analyzes to show the complexities of the Bluetooth specifications and their sensitivity to minor changes (whether in the specifications or in their implementation).

As mobile phones get increasingly complicated the demands for an effective firmware update service increase. A proposed solution is Firmware Over The Air (FOTA) and the Open Mobile Alliance’s Device Management where mobile phones can be updated and managed via the mobile phone network. However, before these operations can be carried out, all FOTA capable mobile phones that should be served must be discovered and registered with a distributor of updates. The information provided must be sufficient to uniquely identify devices, initiate a Device Management session, and determine if a firmware update is needed. This thesis addresses the problems that a solution in automatically collecting this information. Several solutions are presented and their suitability evaluated on the basis of defined and analyzed requirements. The solutions most thoroughly examined are various manual solutions, retrieval of information from core network nodes, and utilizing the Short Message Service (SMS) or Unstructured Supplementary Service Data (USSD). A phone application has been implemented according to the requirements from the Chinese network operator China Mobile Communications Corporation (CMCC). It is a part of a solution in which the information is delivered via a SMS session. The design and development phase of the application is described, accompanied by a brief description of the Symbian OS and the working environment (tools, devices, etc.) needed to implement this solution. This work took place at the Sony Ericsson office in Beijing, China. The application implemented is robust and it is impossible to avoid registration, furthermore the user can not be exposed to acknowledgement messages. It has been made possible on the cost of decreased phone performance (a few kB of memory) since the application runs all the time. Malfunctioning phone or network may hinder registration. / Mobiltelefoner blir ständigt mer komplicerade vilket medför att efterfrågan av en effektiv lösning för uppdateringar av mjukvaran i mobiltelefonerna ökar. Lösningen är Firmware Over The Air (FOTA) och Device Management; mobiltelefonerna uppdateras och sköts via mobiltelefonnätverket. Men innan förfaranden kan exekveras måste alla mobiltelefoner med FOTA som ska omfattas av tjänsten upptäckas och registreras hos den som distribuerar uppdateringarna. Den information som måste levereras måste vara tillräcklig för att kunna identifiera mobiltelefonen, genomföra en Device Management session och avgöra om en uppdatering av mjukvaran är nödvändig. Detta examensarbete behandlar de problem som en lösning i vilken information tillhandahålls möter. Ett flertal lösningar presenteras och deras lämplighet utvärderas på basis av definierade och analyserade krav. De mest ingående undersökta lösningarna är olika manuella lösningar, insamling av information från noderna av kärnnätverket samt utnyttjande av SMS eller USSD. En telefonapplikation har implementeras enligt krav från den kinesiska operatören CMCC. Applikationen är en del av en lösning i vilken informationen levereras via en SMS-session. Applikationens design och utvecklingsfasen är beskriven, samt en översiktlig beskrivning av Symbian operativsystem och utvecklingsmiljön (verktyg, mobiltelefoner, etc.) som behövdes för att implementera lösningen. Detta arbete genomfördes på Sony Ericssons kontor i Beijing, Kina.

Modern heterogeneous networks present a great challenge for network operators and engineers from a management and configuration perspective. The Tail-f Systems’ Network Control System (NCS) is a network management framework that addresses these challenges. NCS offers centralized network configuration management functionality, along with providing options for extending the framework with additional features. The devices managed by NCS are stored in its Configuration Database (CDB). However, currently there is no mechanism for automatically adding network devices to the configuration of NCS, thus each device’s management parameters have to be entered manually. The goal of this master’s thesis project is to develop a software module for NCS that simplifies the process of initial NCS configuration by allowing NCS to automatically add network devices to the NCS CDB. Apart from developing the software module for discovery, this project aims to summarize existing methods and to develop new methods for automated discovery of network devices with the main focus on differentiating between different types of devices. A credential-based device discovery method was developed and utilized to make advantage of known credentials to access devices, which allows for more precise discovery compared to some other existing methods. The selected methods were implemented as a component of NCS to provide device discovery functionality. Another focus of this master’s thesis project was the development of an approach to network topology discovery and its representation. The aim is to provide both a logical Internet Protocol (IP) network topology and a physical topology of device interconnections. The result is that we are able to automatically discover and store the topology representation as a data structure, and subsequently generate a visualization of the network topology. / Moderna heterogena nätverk utgör en stor utmaning för operatörer och ingenjörer att hantera och konfigurera. Tail-f Systems NCS produkt är ett ramverk för nätverks konfiguration som addresserar dessa utmaningar. NCS är ett centraliserat nätverks konfigurations verktyg. NCS är användbart som det är, men kan också byggas ut av användaren med ytterligare funktioner. De enheter som hanteras med NCS lagras i konfigurationsdatabasen (CDB). För närvarande finns det ingen automatiserad mekanism för att addera nätverksenheter till NCS, och varje enhets parametrar måste fyllas i manuellt. Detta examensarbetes mål är att utveckla en mjukvarumodul för NCS som förenklar NCS konfiguration genom att automatiskt lägga nätverksenheter till NCS CDB. Förutom att utveckla programvara för enhetsidentifiering, syftar detta projekt till att sammanfatta befintliga metoder och utveckla nya metoder för automatiserad nätverksenhetsidentifiering med huvudfokus på att skilja mellan olika typer av enheter. En metod baserad på förkonfigurerade autenticeringsuppgifter har utvecklats och den används för att precist kunna identifiera olika typer av nätverkselement. De valda metoderna har implementerats som en optionell modul till NCS som erbjuder enhetsidentifieringsfunktionalitet. Ytterligare ett fokus för detta examensarbete har varit att utveckla metoder för identifieraing av nätverkstopologin, och modeller för hur topologin ska representeras.  Vi har syftat till att identifiera både den logiska IP nätverkstopologin (L3) och den fysiska topologin av sammankopplade enheter (L2). Den viktigaste uppgiften har varit att identifiera och lagra topologi representation som en datastruktur, och dessutom generera en visualisering av nätverkstopologin.

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-09-23T18:25:13Z No. of bitstreams: 1 DissIMF.pdf: 12997797 bytes, checksum: 61ca28804fe846c5e4f1f3d97a366017 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T14:23:42Z (GMT) No. of bitstreams: 1 DissIMF.pdf: 12997797 bytes, checksum: 61ca28804fe846c5e4f1f3d97a366017 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T14:23:49Z (GMT) No. of bitstreams: 1 DissIMF.pdf: 12997797 bytes, checksum: 61ca28804fe846c5e4f1f3d97a366017 (MD5) / Made available in DSpace on 2016-10-10T14:23:59Z (GMT). No. of bitstreams: 1 DissIMF.pdf: 12997797 bytes, checksum: 61ca28804fe846c5e4f1f3d97a366017 (MD5) Previous issue date: 2015-11-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The popularization of mobile devices capable of communicating via wireless network technologies allows us to consider different scenarios in which these devices may autonomously interact with each other. The envisioned communications would occur in a P2P fashion, as each device could simultaneously provide and consume services. A mechanism for dynamically discovering nearby devices and the available services would be necessary. Although a few existing applications already provide the direct interaction among devices they are purpose-specific and rely on pre-configured information for identifying other devices. A service-oriented architecture (SOA), based on HTTP requests and the REST or SOAP protocols, is commonly used in this type of communication. However, automatically finding available known services is still challenging. Service discovery is usually based exclusively on service name, which is not very flexible. This work proposes a new model for the direct interaction between computing devices. In an attempt to facilitate service discovery and selection we propose a content centric model in which interactions are defined according to an object’s type and the action to be applied to it. The proposed approach can workatop of existing discovery protocols, based on extensible metadata fields and on existing service data. Our proposal is evaluated according to i) the viability of direct communication between nearby devices, even when carried by users or associated to vehicles; ii) the proposed service discovery and matching using the content centric approach; iii) the effectiveness of a middleware to support the development of generic applications for direct device communication. Simulation results show our proposed model is viable. A preliminary implementation of the middleware was also evaluated and the results show that spontaneous, opportunistic, service-based interactions among devices can be achieved for different types of services. / A popularização de dispositivos móveis dotados de capacidade de comunicação sem fio possibilita a criação de ambientes onde estes dispositivos interagem diretamente entre si. Essas comunicações ocorrem no modelo P2P, de forma que cada dispositivo pode implementar simultaneamente papéis de cliente e de servidor. Contudo, para que ocorram interações di- retas entre dispositivos através de aplicações, é preciso que estes dispositivos implementem algum mecanismo de descoberta. Atualmente, a maioria das aplicações que se comunicam diretamente utilizam informações pré-configuradas para identificação de dispositivos e serviços. Uma forma utilizada para interação entre dispositivos é através da oferta e consumo de serviços utilizando a arquitetura orientada a serviços (SOA), baseada em requisições HTTP utilizando os padrões REST ou SOAP. Um problema recorrente para consumidores de serviços é a identificação de serviços disponíveis. A identificação utilizada em protoco- los de descoberta existentes baseia-se apenas no nome do serviço, salvo em comunicações pré-configuradas, o que não apresenta flexibilidade para descobrir novos serviços. De forma a facilitar a troca de informações entre dispositivos, este trabalho propõe um modelo em que interações diretas entre dispositivos sejam centradas no conteúdo envolvido na interação e nas ações que se deseja realizar sobre eles. Para tanto, uma identificação de serviço pode ser baseada em metadados que são adicionados às descrições de serviços existentes, ou em informações obtidas com protocolos de descoberta de serviço existentes. Para avaliar o modelo proposto, esse trabalho apresenta um estudo sobre i) a viabilidade de interações diretas entre dispositivos, considerando suas mobilidades; ii) o uso de um modelo de interação centrado em conteúdo e ação; iii) o desenvolvimento de um Middleware para simplificar o desenvolvimento de aplicações que usem o modelo de serviço proposto. Os resultados de simulação obtidos mostram que o modelo é viável. Além disso, uma versão preliminar do Middleware proposto foi avaliada e mostra que a interação direta entre dispositivos pode ocorrer de forma oportunística e espontânea.