Recent advances in hardware, software, and communication technologies are enabling the design and implementation of a whole range of different types of networks that are being deployed in various environments. One such network that has received a lot of interest in the last couple of years is the Vehicular Ad-Hoc Network (VANET). VANET has become an active area of research, standardization, and development because it has tremendous potential to improve vehicle and road safety, traffic efficiency, and convenience as well as comfort to both drivers and passengers. Recent research efforts have placed a strong emphasis on novel VANET design architectures and implementations. A lot of VANET research work have focused on specific areas including routing, broadcasting, Quality of Service (QoS), and security. We survey some of the recent research results in these areas. We present a review of wireless access standards for VANETs, and describe some of the recent VANET trials and deployments in the US, Japan, and the European Union. In addition, we also briefly present some of the simulators currently available to VANET researchers for VANET simulations and we assess their benefits and limitations. Finally, we outline some of the VANET research challenges that still need to be addressed to enable the ubiquitous deployment and widespead adoption of scalable, reliable, robust, and secure VANET architectures, protocols, technologies, and services.

Vehicular ad hoc networks (VANETS): status, results, and challenges

A survey on vehicular cloud computing

Based on a variety of long-term network traffic data from different geographies and applications, in addition to long-term scaling trends of key information and communication technologies, we identify fundamental scaling disparities between the technologies used to generate and process data and those used to transport data. These disparities could lead to the data transport network falling behind its required capabilities by a factor of approximately 4 every five years. By 2024, we predict the need for 10-Tb/s optical interfaces working in 1-Pb/s optical transport systems. To satisfy these needs, multiplexing in both wavelength and space in the form of a wavelength-division multiplexing × space-division multiplexing matrix will be required. We estimate the characteristics of such systems and outline their target specifications, which reveals the need for very significant research progress in multiple areas, from system and network architectures to digital signal processing to integrated arrayed device designs, in order to avoid an optical network capacity crunch.

From Scaling Disparities to Integrated Parallelism: A Decathlon for a Decade

Position-based routing is considered to be a very promising routing strategy for communication within vehicular ad hoc networks (VANETs), due to the fact that vehicular nodes can obtain position information from onboard global positioning system receivers and acquire global road layout information from an onboard digital map. Position-based routing protocols, which are based mostly on greedy forwarding, are well-suited to the highly dynamic and rapid-changing network topology of VANETs. In this paper, we outline the background and the latest development in VANETs and survey the state-of-the-art routing protocols previously used in VANETs. We present the pros and cons for each routing protocol, and make a detailed comparison. We also discuss open issues, challenges and future research directions. It is observed that a hybrid routing protocol is the best choice for VANETs in both urban and highway environments.

A survey on position-based routing for vehicular ad hoc networks

Review: Vehicular communication ad hoc routing protocols: A survey

http://www.it.uc3m.es/cjbc/papers/pdf/2013_bilal_jnca_position.pdf

Position-based routing in vehicular networks: A survey

We investigated the reach increase obtained through nonlinearity mitigation by means of transmission symbol rate optimization (SRO). First, we did this theoretically and simulatively. We showed that the nonlinearity model that properly accounts for the phenomenon is the EGN model, in its version that specifically includes four-wave mixing. We then found that for PM-QPSK systems at full C-band, the reach increase may be substantial, on the order of 10–25%, with optimum symbol rates on the order of 2–6 GBd. We show that for C-band PM-QPSK systems over SMF, the potential mitigation due to SRO is greater than that ideally granted by digital backpropagation (the latter applied over a bandwidth of a 32-GBd channel). We then set up an experiment to obtain confirmation of the theoretical and simulative predictions. It consisted of 19 PM-QPSK channels, operating at 128 Gb/s per channel, over PSCF, with span length 108 km and EDFA-only amplification. We demonstrated a reach increase of about 13.5%, when going from single-carrier per channel transmission, at 32 GBd, to eight subcarrier per channel, at 4 GBd, in line with the EGN model predictions. We also extended the theoretical investigation of SRO to PM-16QAM, where we found a qualitatively similar effect to PM-QPSK, although the potential reach increase appears to be typically only about 50% to 60% that of PM-QPSK. Further investigation is, however, in order, specifically to explore the effect on PM-16QAM SRO of the removal of long-correlated phase and polarization noise.

Analytical and Experimental Results on System Maximum Reach Increase Through Symbol Rate Optimization

Network simulation is the most useful and common methodology used to evaluate different network topologies without real world implementation. Network simulators are widely used by the research community to evaluate new theories and hypotheses. There are a number of network simulators, for instance, ns-2, ns-3, OMNET++, SWAN, OPNET, Jist, and GloMoSiM etc. Therefore, the selection of a network simulator for evaluating research work is a crucial task for researchers. The main focus of this paper is to compare the state-of-the-art, open source network simulators based on the following parameters: CPU utilization, memory usage, computational time, and scalability by simulating a MANET routing protocol, to identify an optimal network simulator for the research community.

A performance comparison of open source network simulators for wireless networks

In this paper, a simple novel digital modulation format identification (MFI) scheme for coherent optical systems is proposed. The scheme is based on the evaluation of the peak-to-average-power ratio (PAPR) of the incoming data samples after analog-to-digital conversion (ADC), chromatic dispersion (CD) and polarization mode demultiplexing (PMD) compensation at the receiver (Rx). Since at a particular optical-signal-to-noise ratio (OSNR) value different modulation formats have distinct PAPR values, it is possible to identify them. The proposed scheme and the results are analyzed both experimentally and through numerical simulations. The results demonstrate successful identification among four modulation formats (MF) commonly used in digital coherent systems.

Blind modulation format identification for digital coherent receivers

Routing in infrastructure less vehicular ad hoc networks is challenging because of the dynamic network, predictable topology, high speed of nodes, and predictable mobility patterns. This paper presents an enhanced routing protocol specifically designed for city environments. It uses vehicular speed and directional density for dynamic junction selection. Simulation results exhibit increased packet delivery ratio while decreased end*to*end delay when compar ed with state of the art protocols.

/pdf/enhanced-junction-selection-mechanism-for-routing-protocol-2oyro50hwr.pdf

Syed Muhammad Bilal

Papers

Position-based routing in vehicular networks: A survey

Analytical and Experimental Results on System Maximum Reach Increase Through Symbol Rate Optimization

A performance comparison of open source network simulators for wireless networks

Blind modulation format identification for digital coherent receivers

Enhanced Junction Selection Mechanism for Routing Protocol in VANETs