11 research outputs found
Secure Data Offloading Strategy for Connected and Autonomous Vehicles
Connected and Automated Vehicles (CAVs) are expected to constantly interact
with a network of processing nodes installed in secure cabinets located at the
side of the road -- thus, forming Fog Computing-based infrastructure for
Intelligent Transportation Systems (ITSs). Future city-scale ITS services will
heavily rely upon the sensor data regularly off-loaded by each CAV on the Fog
Computing network. Due to the broadcast nature of the medium, CAVs'
communications can be vulnerable to eavesdropping. This paper proposes a novel
data offloading approach where the Random Linear Network Coding (RLNC)
principle is used to ensure the probability of an eavesdropper to recover
relevant portions of sensor data is minimized. Our preliminary results confirm
the effectiveness of our approach when operated in a large-scale ITS networks.Comment: To appear in IEEE VTC-Spring 201
On Intercept Probability Minimization under Sparse Random Linear Network Coding
This paper considers a network where a node wishes to transmit a source
message to a legitimate receiver in the presence of an eavesdropper. The
transmitter secures its transmissions employing a sparse implementation of
Random Linear Network Coding (RLNC). A tight approximation to the probability
of the eavesdropper recovering the source message is provided. The proposed
approximation applies to both the cases where transmissions occur without
feedback or where the reliability of the feedback channel is impaired by an
eavesdropper jamming the feedback channel. An optimization framework for
minimizing the intercept probability by optimizing the sparsity of the RLNC is
also presented. Results validate the proposed approximation and quantify the
gain provided by our optimization over solutions where non-sparse RLNC is used.Comment: To appear on IEEE Transactions on Vehicular Technolog
Operating ITS-G5 DSRC over Unlicensed Bands: A City-Scale Performance Evaluation
Future Connected and Autonomous Vehicles (CAVs) will be equipped with a large
set of sensors. The large amount of generated sensor data is expected to be
exchanged with other CAVs and the road-side infrastructure. Both in Europe and
the US, Dedicated Short Range Communications (DSRC) systems, based on the IEEE
802.11p Physical Layer, are key enabler for the communication among vehicles.
Given the expected market penetration of connected vehicles, the licensed band
of 75 MHz, dedicated to DSRC communications, is expected to become increasingly
congested. In this paper, we investigate the performance of a vehicular
communication system, operated over the unlicensed bands 2.4 GHz - 2.5 GHz and
5.725 GHz - 5.875 GHz. Our experimental evaluation was carried out in a testing
track in the centre of Bristol, UK and our system is a full-stack ETSI ITS-G5
implementation. Our performance investigation compares key communication
metrics (e.g., packet delivery rate, received signal strength indicator)
measured by operating our system over the licensed DSRC and the considered
unlicensed bands. In particular, when operated over the 2.4 GHz - 2.5 GHz band,
our system achieves comparable performance to the case when the DSRC band is
used. On the other hand, as soon as the system, is operated over the 5.725 GHz
- 5.875 GHz band, the packet delivery rate is 30% smaller compared to the case
when the DSRC band is employed. These findings prove that operating our system
over unlicensed ISM bands is a viable option. During our experimental
evaluation, we recorded all the generated network interactions and the complete
data set has been publicly available.Comment: IEEE PIMRC 2019, to appea
Completion Delay of Random Linear Network Coding in Full-Duplex Relay Networks
As the next-generation wireless networks thrive, full-duplex and relaying
techniques are combined to improve the network performance. Random linear
network coding (RLNC) is another popular technique to enhance the efficiency
and reliability in wireless communications. In this paper, in order to explore
the potential of RLNC in full-duplex relay networks, we investigate two
fundamental perfect RLNC schemes and theoretically analyze their completion
delay performance. The first scheme is a straightforward application of
conventional perfect RLNC studied in wireless broadcast, so it involves no
additional process at the relay. Its performance serves as an upper bound among
all perfect RLNC schemes. The other scheme allows sufficiently large buffer and
unconstrained linear coding at the relay. It attains the optimal performance
and serves as a lower bound among all RLNC schemes. For both schemes,
closed-form formulae to characterize the expected completion delay at a single
receiver as well as for the whole system are derived. Numerical results are
also demonstrated to justify the theoretical characterizations, and compare the
two new schemes with the existing one
A protocol design paradigm for rateless fulcrum code
Establecer servicios Multicast eficientes en una red con dispositivos heterog茅neos y bajo los efectos de un canal con efecto de borradura es una de las prioridades actuales en la teor铆a de la codificaci贸n, en particular en Network Coding (NC). Adem谩s, el creciente n煤mero de clientes con dispositivos m贸viles de gran capacidad de procesamiento y la prevalencia de tr谩fico no tolerante al retardo han provocado una demanda de esquemas Multicast sin realimentaci贸n en lo que respecta a la gesti贸n de recursos distribuidos. Las plataformas de comunicaci贸n actuales carecen de un control de codificaci贸n gradual y din谩mico basado en el tipo de datos que se transmiten a nivel de la capa de aplicaci贸n. Este trabajo propone un esquema de transmisi贸n fiable y eficiente basado en una codificaci贸n hibrida compuesta por una codificaci贸n sistem谩tica y codificaci贸n de red lineal aleatoria (RLNC) denominada codificaci贸n Fulcrum. Este esquema h铆brido de codificaci贸n distribuida tipo Rateless permite implementar un sistema adaptativo de gesti贸n de recursos para aumentar la probabilidad de descodificaci贸n durante la recepci贸n de datos en cada nodo receptor de la informaci贸n. En 煤ltima instancia, el esquema propuesto se traduce en un mayor rendimiento de la red y en tiempos de transmisi贸n (RTT) mucho m谩s cortos mediante la implementaci贸n eficiente de una correcci贸n de errores hacia delante (FEC).DoctoradoDoctor en Ingenier铆a de Sistemas y Computaci贸