7 research outputs found
Delay Tolerant Networks for Efficient Information Harvesting and Distribution in Intelligent Transportation Systems
[EN] Intelligent Transportation Systems (ITS) can make transportation safer, more efficient, and more sustainable
by applying various information and communication technologies. One of these technologies are \acfp{VN}.
\acp{VN} combine different communication solutions such as cellular networks,
\acfp{VANET}, or IEEE 802.11 technologies to provide connectivity among
vehicles, and between vehicles and road infrastructure.
This thesis focuses on VNs, and considers that the high speed of the nodes
and the presence of obstacles like buildings, produces a highly variable network
topology, as well as more frequent partitions in the network. Therefore,
classical \ac{MANET} protocols do not adapt well to VANETs. Under these
conditions, \ac{DTN}
have been proposed as an alternative able to cope with these adverse
characteristics. In DTN, when a message cannot be routed
to its destination, it is not immediately dropped but it is instead stored and
carried until a new route becomes available. The combination of VN and
DTN is called \acp{VDTN}.
In this thesis, we propose a new VDTN protocol designed to collect
information from vehicular sensors. Our proposal, called \ac{MSDP}, combines
information about the localization obtained from a GNSS system with the actual
street/road layout obtained from a Navigation System (NS) to define a new
routing metric. Both analytical and simulation results prove that MSDP outperforms
previous proposals.
Concerning the deployment of VNs and VANET technologies, technology
already left behind the innovation and the standardization phases, and it is
about time it reach the first early adopters in the market. However, most car
manufacturers have decided to implement VN devices in the form of On Board
Units (OBUs), which are expensive, heavily manufacturer dependent, and
difficult to upgrade. These facts are delaying the deployment of VN. To boost
this process, we have developed the GRCBox architecture. This architecture is
based on low-cost devices and enables the establishment of V2X, \emph{i.e.} V2I and V2V, communications
while integrating users by easing the use of general purpose devices like
smartphones, tablets or laptops. To demonstrate the viability of the GRCBox
architecture, we combined it with a DTN platform called Scampi to obtain
actual results over a real VDTN scenario. We also
present several GRCBox-aware applications that illustrate how developers can
create applications that bring the potential of VN to user devices.[ES] Los sistemas de transporte inteligente (ITS) son el soporte para el establecimiento de un
transporte más seguro, más eficiente y más sostenible mediante el uso de
tecnologías de la información y las comunicaciones.
Una de estas tecnologías son las redes vehiculares
(VNs). Las VNs combinan diferentes tecnologías de comunicación como las redes
celulares, las redes ad-hoc vehiculares (VANETs) o las redes 802.11p para
proporcionar conectividad entre vehículos, y entre vehículos y la
infraestructura de carreteras.
Esta tesis se centra en las VNs, en las cuales la alta velocidad de los
nodos
y la presencia de obstáculos como edificios producen una topología de red
altamente variable, así como frecuentes particiones en la red. Debido a estas características,
los protocolos para redes móviles ad-hoc (MANETs) no se adaptan bien a las
VANETs. En estas condiciones, las redes tolerantes a retardos (DTNs) se han
propuesto como una alternativa capaz de hacer frente a estos problemas. En DTN,
cuando un mensaje no puede ser encaminado hacia su destino, no es
inmediatamente descartado sino es almacenado hasta que una nueva ruta esta disponible.
Cuando las VNs y las DTNs se combinan surgen las redes vehiculares tolerantes
a retardos (VDTN).
En esta tesis proponemos un nuevo protocolo para VDTNs diseñado para recolectar
la información generada por sensores vehiculares. Nuestra propuesta, llamada
MSDP, combina la información obtenida del servicio de información geográfica
(GIS) con el mapa real de las calles obtenido del sistema de navegación (NS)
para definir una nueva métrica de encaminamiento. Resultados analíticos y
mediante simulaciones prueban que MSDP mejora el rendimiento de propuestas
anteriores.
En relación con el despliegue de las VNs y las tecnologías VANET, la
tecnología ha dejado atrás las fases de innovación y estandarización,
ahora es el momento de alcanzar a los primeros usuarios del mercado. Sin embargo,
la mayoría de fabricantes han decidido implementar los dispositivos para VN
como unidades de a bordo (OBU), las cuales son caras y difíciles de
actualizar. Además, las OBUs son muy dependientes del fabricante original.
Todo esto esta retrasando el despliegue de las VNs. Para acelerar la adopción
de las VNs, hemos desarrollado la arquitectura GRCBox. La arquitectura GRCBox
esta basada en un dispositivo de bajo coste que permite a los usuarios usar
comunicaciones V2X (V2V y V2I) mientras utilizan dispositivos de propósito general como
teléfonos inteligentes, tabletas o portátiles. Las pruebas incluidas en esta
tesis demuestran la viabilidad de la arquitectura GRCBox. Mediante la
combinación de nuestra GRCBox y una plataforma de DTN llamada Scampi hemos
diseñado y probado un escenario VDTN real. También presentamos como los
desarrolladores pueden crear nuevas aplicaciones GRCBox para llevar el
potencial de las VN a los dispositivos de usuario.[CA] Els sistemes de transport intel·ligent (ITS) poden crear un transport més
segur, més eficient i més sostenible mitjançant l'ús de tecnologies de la
informació i les comunicacions aplicades al transport.
Una d'aquestes tecnologies són les xarxes vehiculars (VN). Les VN combinen
diferents tecnologies de comunicació, com ara les xarxes cel·lulars, les
xarxes ad-hoc vehiculars (VANET) o les xarxes 802.11p, per a proporcionar
comunicació entre vehicles, i entre vehicles i la infraestructura de
carreteres.
Aquesta tesi se centra en les VANET, en les quals l'alta velocitat dels nodes
i la presència d'obstacles, com els edificis, produeixen una topologia de
xarxa altament variable, i també freqüents particions en la xarxa. Per aquest
motiu, els protocols per a xarxes mòbils ad-hoc (MANET) no s'adapten bé. En
aquestes condicions, les xarxes tolerants a retards (DTN) s'han proposat com
una alternativa capaç de fer front a aquests problemes. En DTN, quan un
missatge no pot ser encaminat cap a la seua destinació, no és immediatament
descartat sinó que és emmagatzemat fins que apareix una ruta nova.
Quan les VN i les DTN es combinen sorgeixen les xarxes vehicular tolerants a
retards (VDTN).
En aquesta tesi proposem un nou protocol per a VDTN dissenyat per a
recol·lectar la informació generada per sensors vehiculars. La nostra
proposta, anomenada MSDP, combina la informació obtinguda del servei
d'informació geogràfica (GIS) amb el mapa real dels carrers obtingut del
sistema de navegació (NS) per a definir una nova mètrica d'encaminament.
Resultats analítics i mitjançant simulacions proven que MSDP millora el
rendiment de propostes prèvies.
En relació amb el desplegament de les VN i les tecnologies VANET, la
tecnologia ha deixat arrere les fases d'innovació i estandardització, ara és
temps d'aconseguir als primers usuaris del mercat. No obstant això, la majoria
de fabricants han decidit implementar els dispositius per a VN com a unitats
de bord (OBU), les quals són cares i difícils d'actualitzar. A més, les OBU
són molt dependents del fabricant original. Tot això està retardant el
desplegament de les VN.
Per a accelerar l'adopció de les VN, hem desenvolupat l'arquitectura GRCBox.
L'arquitectura GRCBox està basada en un dispositiu de baix cost que permet als
usuaris usar comunicacions V2V mentre usen dispositius de propòsit general,
com ara telèfons intel·ligents, tauletes o portàtils. Les proves incloses en
aquesta tesi demostren la viabilitat de l'arquitectura GRCBox. Mitjançant la
combinació de la nostra GRCBox i la plataforma de DTN Scampi, hem dissenyat i
provat un escenari VDTN pràctic. També presentem com els desenvolupadors poden
crear noves aplicacions GRCBox per a portar el potencial de les VN als
dispositius d'usuari.Martínez Tornell, S. (2016). Delay Tolerant Networks for Efficient Information Harvesting and Distribution in Intelligent Transportation Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/68486TESI
A Tool Offering Steady-State Simulations for VANETs
[EN] Without realistic vehicle mobility patterns, the evaluation of communication protocols in vehicular networks is compromised. Moreover, in order to ensure repeatability and fairness in vehicular simulations, researchers require simulation tools that allow them to have a complete control of simulations. In this paper we present VACaMobil, a Mobility Manager for the OMNeT++ simulator which offers a way to create complex scenarios with realistic vehicular mobility by allowing to define the desired average number of vehicles, along with its upper and lower bounds, which are maintained throughout the simulation. We compare VACaMobil against other commonly used methods which also generate and manage vehicular mobility. Results expose some flaws of those basic tools, and shows that VACaMobil behaves significantly better. The harmful impact on communication protocols when using common tools is also quantified, revealing VACaMobil as a necessity for current research.This work was partially supported by the Ministerio de Economía y Competitividad, Spain, under Grants TIN2011-27543- C03-01 and BES-2012-052673, by the Ministerio de Educación, Spain, under the FPU program, AP2010-4397, AP2009-2415, and by the Universitat Politècnica de València under project ABATIS (PAID-05-12).Báguena Albaladejo, M.; Martínez Tornell, S.; Torres Cortés, Á.; Calafate, CT.; Cano Escribá, JC.; Manzoni, P. (2013). A Tool Offering Steady-State Simulations for VANETs. Recent Patents on Telecommunications. 2(2):102-112. http://hdl.handle.net/10251/40658S1021122
An analytical evaluation of a Map-based Sensor-data Delivery Protocol for VANETs
© 2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The Delay Tolerant Networks (DTN) approach is
considered the best strategy to address the specific issues of
the VANETs, namely high mobility, variable node density or
frequent radio obstacles. Several protocols have been proposed
for DTNs, being the epidemic routing (and variations of it)
the most representative protocol. Nevertheless, the availability
of navigation systems, thanks to which each vehicle is aware of
its location within a map, introduces the possibility for a new
routing approach, known as Geographic Routing.
In this paper we analytically evaluate the performance of our
previously presented Map-based Sensor-data Delivery Protocol
(MSDP). We introduce an analytical model that takes into
account the effect of constrained buffers. The results show that
adopting the Map-based Sensor-data Delivery Protocol (MSDP)
routing mechanism allows achieving a reasonable delivery time
with an insignificant overhead compared with epidemic routing.This work was partially supported by the Ministerio de Ciencia e Innovación, Spain, under Grants TIN2011-27543-C03-01 and BES-2012-052673.Martínez Tornell, S.; Hernández Orallo, E.; Tavares De Araujo Cesariny Calafate, CM.; Cano Escribá, JC.; Manzoni, P. (2013). An analytical evaluation of a Map-based Sensor-data Delivery Protocol for VANETs. IEEE. https://doi.org/10.1109/WoWMoM.2013.6583405
Evaluating the feasibility of using smartphones for ITS safety applications
“©2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Driving security and comfort can be improved by
applying Intelligent Transportation Systems (ITS) proposals. The
low adoption rate of new ITS hardware and software products is
slowing down the market introduction of these solutions. In this
paper we present a driving safety application for smartphones
based on a warning dissemination protocol called eMDR.
The use of smartphones minimizes the hardware cost and
eliminates most of the adoption barriers; users will no longer have
to install new dedicated devices in their vehicles. Instead, they will
simply have to install an application in their smartphone. Our
application is integrated with a Navigation System which provides
access to road maps, current location, and route information.
We analyzed the behavior of the wireless channel and the GPS
location service under different conditions to assess the feasibility
of our proposal. Results showed that, in C2C communications,
smartphones are able to provide a reasonable degree of connectivity,
and that the degree of precision achieved is enough for
certain types of driving safety applications.This work was partially supported by the Ministerio de Ciencia e Innovación, Spain, under Grants TIN2011-27543-C03-01 and BES-2012-052673.Tornell, SM.; Tavares De Araujo Cesariny Calafate, CM.; Cano Escribá, JC.; Manzoni, P.; Fogue, M.; Martínez, FJ. (2013). Evaluating the feasibility of using smartphones for ITS safety applications. IEEE. https://doi.org/10.1109/VTCSpring.2013.6692553
Diseño de un protocolo para redes tolerantes a retardos: RTaDAP
[EN] In last years the European Commission has decided to make an e ort in order
to improve road tra c security. One of the main lines which this e ort is divided in is the
Intelligent Transportation System technology, which aims to increase e cient and security
of road tra c using new communication techniques. The number of techniques used for
this purpose varies from vehicular ad-hoc networks to cellular mobile networks. Inside this
wide range of protocols and technologies we have focused in delay tolerant networks and
how it can be applied to vehicular networks facing the intermittent connectivity due to
rapid changes of its topology. We have studied the proposed protocols and identi ed the
main gaps needed to be lled in them, joining all this gaps and trying to ll most of them
we have designed, developed and tested our own DTN protocol based on tra c route
topology awareness called Road Topology and Destination Aware Protocol (RTaDAP).
Testing results, based on simulations, shown that our protocol behaves better than well
known DTN protocols under some conditions but presents some problems that must be
solved in future.Martínez Tornell, S. (2012). Diseño de un protocolo para redes tolerantes a retardos: RTaDAP. http://hdl.handle.net/10251/27339