An intelligent network selection mechanism for vertical handover decision in vehicular Ad Hoc wireless networks

The design of the Vehicular Ad-hoc Network (VANET) technology is a modern paradigm for vehicular communication on movement. However, VANET's vertical handover (VHO) decision in seamless connectivity is a huge challenge caused by the network topology complexity and the large number of mobile nodes that affect the network traffic in terms of the data transmission and dissemination efficiency. Furthermore, the conventional scheme only uses a received signal strength as a metric value, which shows a lack of appropriate handover metrics that is more suitable in horizontal handover compared to VHO. Appropriate VHO decisions will result in an increase in the network quality of service (QoS) in terms of delay, latency, and packet loss. This study aims to design an intelligent network selection to minimize the handover delay and latency, and packet loss in the heterogeneous Vehicle-to- Infrastructure (V2I) wireless networks. The proposed intelligent network selection is known as the Adaptive Handover Decision (AHD) scheme that uses Fuzzy Logic (FL) and Simple Additive Weighting (SAW) algorithms, namely F-SAW scheme. The AHD scheme was designed to select the best-qualified access point (AP) and base station (BS) candidates without degrading the performance of ongoing applications. The F-SAW scheme is proposed to develop a handover triggering mechanism that generates multiple attributes parameters using the information context of vertical handover decision in the V2I heterogeneous wireless networks. This study uses a network simulator (NS-2) as the mobility traffic network and vehicular mobility traffic (VANETMobiSim) generator to implement a topology in a realistic VANET mobility scenario in Wi-Fi, WiMAX, and LTE networks technologies. The proposed AHD scheme shows an improvement in the QoS handover over the conventional (RSS-based) scheme with an average QoS increased of 21%, 20%, and 13% in delay, latency and packet loss, while Media Independent Handover based (MIH-based) scheme with 12.2%, 11%, and 7% respectively. The proposed scheme assists the mobile user in selecting the best available APs or BS during the vehicles’ movement without degrading the performance of ongoing applications

Evaluating WIMAX for real-time vehicular communications

Mestrado em Engenharia Electrónica e TelecomunicaçõesOs acidentes rodoviários têm um impacto elevado na sociedade, quer devido às perdas humanas daí resultantes quer devido aos custos económicos associados. Este facto tem causado por todo o mundo o estudo de mecanismos que permitam aumentar a segurança rodoviária. Um exemplo disto é o investimento da Europa em vários projectos com vista a desenvolver estes mecanismos, onde a maior parte destas iniciativas consideram a possibilidade dos veículos comunicarem entre si e/ou com estações fixas, situadas junto da rodovia. A mobilidade dos veículos apresenta requisitos especiais, onde as comunicações sem-fios têm um papel crucial nestas aplicações. Contudo, os serviços de segurança rodoviária requerem alguns requisitos específicos, como largura de banda ou em termos de timeliness, que têm de ser cumpridos independentemente da tecnologia sem-fios usada. Neste trabalho é pretendido avaliar WiMAX para comunicações relacionadas com a segurança rodoviária, em que a coexistência de diferentes tipos de serviços é uma realidade, onde o uso dos mecanismos de qualidade de serviço fornecidos pelo WiMAX podem ser uma vantagem. ABSTRACT: Road accidents have a huge impact on the society, both because of the resulting human life losses and injuries as well as because of the associ- ated economic costs. This situation fostered the study of mechanisms for increasing road safety all over the world. In Europe, several projects are being funded to develop such mechanisms. Many of the approaches that are being pursued require the ability of the vehicles to communicate with each other and/or with fixed roadside equipments. Due to the mobility con- straints, wireless technologies have a crucial role in this kind of applications. However, road safety services have also specific demands, in terms of band- width and timeliness, that have to be met, independently of the wireless technology used. In this work, it is performed an evaluation of WiMAX for road safety communications, taking into consideration the coexistence of different types of service and that the use of quality of service mechanisms in this wireless technology could be an advantage

Vehicular networks : IEEE 802.11p analysis and integration into an heterogeneous WMN

Tese de Mestrado Integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 201

Assessing WiMAX for vehicular communications applications

Mestrado em Engenharia Electrónica e TelecomunicaçõesOs acidentes rodoviários têm um enorme impacto na sociedade, quer devido às perdas humanas daí resultantes quer devido aos custos económicos a si associados. Por todo o mundo, esta situação levou ao estudo de mecanismos que permitem aumentar a segurança nas estradas. Por exemplo, na Europa estão a ser financiados vários projectos para desenvolver estes mecanismos e a maior parte das iniciativas em curso requerem a possibilidade dos veículos comunicarem entre si e/ou com estações que se encontram fixas junto à estrada. Devido aos requisitos de mobilidade dos veículos, as tecnologias de comunicação sem fios têm um papel crucial neste tipo de aplicações. Neste sentido, esta dissertação avalia a adequação da tecnologia de comunicação sem fios WiMAX para a transmissão de serviços de segurança rodoviária e/ou outros, entre os veículos e a infraestrutura, usando para isso os mecanismos integrados de diferenciação de tráfego desta mesma tecnologia de comunicação. Especificamente, o objectivo é avaliar se estes mecanismos são apropriados para fornecer os serviços atrás mencionados tendo em conta os seus requisitos tempo-real (largura de banda, latência, variação da latência, etc.).Road accidents have a huge impact on the society, both because of the resulting human life losses and injuries as well as because of the associated economic costs. This situation fostered the study of mechanisms for increasing road safety all over the world. In Europe, several projects are being funded to develop such mechanisms. Many of the approaches that are being pursued require the ability of the vehicles to communicate with each other and/or with fixed roadside equipments. Due to the mobility constraints, wireless technologies have a crucial role in this kind of applications. This dissertation assesses the suitability of the WiMAX wireless technology for supplying vehicle to infrastructure road safety services and others, using this communication technology integrated quality of service mechanisms that provides traffic differentiation. Specifically, the purpose is to evaluate if these mechanisms are appropriate to provide the referred services taking in account their real-time requirements (bandwidth, latency, jitter, etc.)

Handoff management for infotainment services over vehicular networks

Intelligent Transportation Systems (ITS) has impulsed the vehicular communications at the present time. The vehicular communications field is a hot research topic and is attracting a great interest in the automotive industry and telecommunications. There are essentially two main lines of work: (1) communication services related to road safety and traffic information; and (2) information and entertainment services, also named infotainment services. These latter services include both transmitting multimedia (voice over IP, streaming, on-line gaming, etc.) and classic data services (e-mail, access to private networks, web browsing, file sharing, etc.). In this thesis we will focus on these infotainment services because further research in this immature research field is necessary and, until nowadays, the main effort of the research community regarding vehicular communication has been focused on road safety and traffic information. Vehicular nodes need to be reached from the Internet and vice versa to be able to access to infotainment services. While vehicles move along the road infrastructure, they change their wireless point of attachment to the network. During this process, connectivity breaks down until the vehicle is connected again to a new road side unit in its area. This disconnection causes a disruption in the communications. Fast handoffs are a crucial requirement for vehicular networks to avoid long disruption times, since the high speed of vehicular nodes involves suffering a lot of handoffs during an Internet connection. This thesis is focused on Vehicular-to-Infrastructure (V2I) real-time infotainment services. The main contributions of this thesis are: i) a new testing framework for V2I communications to be able to test infotainment services in an easy way; ii) the analysis of the deployability of infotainment video services in vehicular networks using mobility protocols; and iii) the development of a new TCP architecture that will provide a better performance for all TCP-based infotainment services in a vehicular scenario with handoffs. In this thesis, firstly, we propose a new testing framework for vehicular infotainment applications. This framework is a vehicular emulation platform that allows testing real applications installed on Linux virtual machines. Using emulation, we are able to evaluate the performance of real applications with real-time requirements, so we can test multimedia applications used to offer infotainment services in vehicular scenarios in a straightforward way. Secondly, using the testing framework implemented in the first part of the thesis, we have done a performance evaluation of an infotainment service. Among these services, we think that video on demand services on highways will be interesting for users, and generate revenue to network operators. So we evaluated how network-layer handoffs can limit the deployment of a video streaming service. According to the results obtained, driving at high speeds will be an issue for a correct playback of video content, even using fast handoffs techniques. Finally, we developed a new TCP architecture to enhance performance during handoffs. Most of the non-safety services on ITS rely on the Transport Control Protocol (TCP), one of the core protocols of the Internet Protocol Suite. However there exists several issues related to TCP and mobility that can affect to TCP performance, and these issues are particularly important in vehicular networks due to its high mobility. Using new IEEE 802.21 MIH services, we propose a new TCP architecture that is able to anticipate handoffs, permitting to resume the communication after a handoff, avoiding long delays caused by TCP issues and adapting the TCP parameters to the new characteristics of the network. Using the architecture proposed, the performance of TCP is enhanced, getting a higher overall throughput and avoiding TCP fairness issues between users.Els Sistemes de Transport Intel·ligents (ITS) han impulsat les comunicacions vehiculars en l'actualitat. Les comunicacions vehiculars és un camp d'investigació de moda, i està atraient un gran interès en la indústria automobilística i de les telecomunicacions. En el camp de les comunicacions vehiculars, hi ha principalment dues línies de treball: (1) serveis de comunicacions relacionats amb la seguretat viària i la informació del trànsit; i (2) serveis d'informació i entreteniment, també anomenats serveis d'infotainment. Aquests últims inclouen tant serveis multimèdia (veu sobre IP, streaming, jocs on-line, etc.), com serveis clàssics de dades (correu electrònic, accés a xarxes privades, navegació web, compartir arxius, etc.). En aquesta tesi ens centrarem en aquests serveis d'infotainment ja que és necessari aprofundir en la investigació per aquests tipus de serveis, ja que, fins avui, els esforços de la comunitat científica en el camp de les comunicacions vehiculars s'ha centrat en els serveis relacionats amb la seguretat viària i la informació del trànsit. Els nodes vehiculars necessiten tenir connexió a Internet per a poder tenir accés als serveis d'infotainment. Mentre els vehicles estan en moviment a través de la xarxa viària, els vehicles han d'anar canviant el punt de connexió sense fils amb la xarxa. Durant aquest procés de canvi de punt de connexió, anomenat handoff, es perd la connectivitat fins que el vehicle es reconnecta a un altre punt de connexió viària prop de la seva àrea. Aquesta desconnexió causa interrupcions en les comunicacions. Uns handoffs ràpids són bàsics a les xarxes vehiculars per a evitar llargs períodes d'interrupció durant les comunicacions, ja que la gran velocitat a la que es mouen els nodes vehiculars significa un gran nombre de handoffs durant una connexió a Internet. Aquesta tesi es centra en serveis d'infotaiment en temps real per a comunicacions Vehicle-a-Infraestructura (V2I). Les principals contribucions d'aquesta tesi son: i) un nou marc de proves per a les comunicacions (V2I) per a poder provar serveis d'infotainment d'una manera fàcil; ii) l'anàlisi de la viabilitat del desplegament de serveis d'infotainment de vídeo en xarxes vehiculars utilitzant protocols de mobilitat IP; i iii) el desenvolupament d'una nova arquitectura TCP que proporciona un millor funcionament per a tots aquells serveis d'infotainment basats en el protocol TCP en un escenari vehicular amb handoffs. En aquesta tesi, primer proposem un nou marc de proves per a aplicacions vehiculars d'infotainment. Aquest marc és una plataforma d'emulació vehicular que permet provar aplicacions reals instal·lades en màquines virtuals Linux. Utilitzant l'emulació, som capaços d'avaluar el rendiment d'aplicacions reals amb característiques de temps real. D'aquesta manera es poden avaluar aplicacions multimèdia utilitzades per oferir serveis d'infotainment d'una forma senzilla en escenaris vehiculars. Segon, utilitzant el marc de prova implementat en la primera part de la tesi, hem avaluat el rendiment d'un servei d'infotainment. Entre aquest tipus de servei, creem que els serveis de vídeo sota demanda en autopistes/autovies serà interessant pels usuaris i generarà beneficis per als operadors de la xarxa. Per tant, hem avaluat com els handoffs a nivell de la capa de xarxa poden limitar el desplegament d'un servei de streaming de vídeo sota demanda. D'acord amb els resultats obtinguts, conduir a grans velocitats podria ser un problema per a poder reproduir un vídeo correctament, tot i utilitzar tècniques de handoffs ràpids. Finalment, hem desenvolupat una nova arquitectura TCP per a millorar el rendiment del protocol durant els handoffs. La majoria dels serveis d'infotainment utilitzen el Protocol de Control de Transport (TCP), un dels principals protocols de la pila de protocols d'Internet. Però existeixen forces problemes relacionats amb l'ús de TCP i la mobilitat que n'afecta el rendiment, i aquests problemes són particular

Distributed All-IP Mobility Management Architecture Supported by the NDN Overlay

Two of the most promising candidate solutions for realizing the next-generation all-IP mobile networks are Mobile IPv6 (MIPv6), which is the host-based and global mobility supporting protocol, and Proxy MIPv6 (PMIPv6), which is the network-based and localized mobility supporting protocol. However, the unprecedented growth of mobile Internet traffic has resulted in the development of distributed mobility management (DMM) architecture by the Internet engineering task force DMM working group. The extension of the basic MIPv6 and PMIPv6 to support their distributed and scalable deployment in the future is one of the major goals of the DMM working group. We propose an all-IP-based mobility management architecture that leverages the concept of Named Data Networking (NDN), which is a distributed content management and addressing architecture. In the proposed solution, mobility support services are distributed among multiple anchor points at the edge of the network, thereby enabling a flat architecture that exploits name-based routing in NDN. Our approach overcomes some of the major limitations of centralized IP mobility management solutions, by extending existing routing protocol and mobility management architecture, to distribute the mobility management function of anchor points in the IP network and optimize the transmission path of mobile traffic