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Electric Vehicles (EVs) are spreading fast as they promise to provide better performances and comfort, but above all, to help facing climate change. Despite their success, their cost is still a challenge. One of the most expensive components of EVs is lithium-ion batteries, which became the standard for energy storage in a wide range of applications. Precisely estimating the Remaining Useful Life (RUL) of battery packs can open to their reuse and thus help to reduce the cost of EVs and improve sustainability. A correct RUL estimation can be used to quantify the residual market value of the battery pack. The customer can then decide to sell the battery when it still has a value, i.e., before it exceeds its end of life of the target application and can still be reused in a second domain without compromising safety and reliability. In this paper, we propose to use a Deep Learning approach based on LSTMs and Autoencoders to estimate the RUL of li-ion batteries. Compared to what has been proposed so far in the literature, we employ measures to ensure the applicability of the method also in the real deployed application. Such measures include (1) avoid using non-measurable variables as input, (2) employ appropriate datasets with wide variability and different conditions, (3) do not use cycles to define the RUL.

Six years after the adoption of the standard 4.0, the Bluetooth Special Interest Group (SIG), a non-profit association that deals with the study and the development of technology standards including those of Bluetooth, has officially released the main features of Bluetooth 5.0. It is one of the significant developments in short-range wireless communication technology. As stated by the SIG, the new standard will forever change the way people approach the Internet of Things (IoT), turning it into something that takes place around them in an almost natural and transparent way. In this article, the future IoT scenarios and use cases that justify the push for Bluetooth 5 are introduced. A set of new technical features that are included in Bluetooth 5 are presented, and their advantages and drawbacks are described., Comment: 17 pages, 3 figures, 3 tables, 15 references, IEEE Communications Magazine journal

Port scans are typically at the begin of a chain of events that will lead to the attack and exploitation of a host over a network. Since building an effective defense relies on information what kind of threat an organization is facing, threat intelligence outlining an actor’s modus operandi is a critical ingredient for network security. In this paper, we describe characteristic patterns in port scan packets that can be used to identify the tool chain used by an adversary. In an empirical analysis of scan traffic received by two /16 networks, we find that common open source port scan tools are adopted differently by communities across the globe, and that groups specializing to use a particular tool have also specialized to exploit particular services.

Mobility has become a basic premise of network communications, thereby requiring a native integration into 5G networks. Despite the numerous efforts to propose and to standardize effective mobility management models for IP, the result is a complex, poorly flexible set of mechanisms. The natural support for mobility offered by ICN (Information Centric Networking), makes it a good candidate to define a radically new solution relieving limitations of traditional approaches. If consumer mobility is supported in ICN by design, in virtue of its connectionless pull-based communication model, producer mobility is still an open challenge. In this work, we propose MAP-Me, an anchor-less solution to manage micro mobility of content producer via ICN name-based data plane, with support for latency-sensitive applications. First, we analyze MAP-Me performance and provide guarantees of correctness and stability. Further, we set up a realistic simulation environment in NDNSim 2.1 for MAP-Me evaluation and comparison against existing solutions: either random waypoint and trace-driven car mobility patterns are considered under 802.11 radio access. Results are encouraging and highlight the superiority of MAP-Me in terms of user performance and of network cost metrics.

On behalf of the Organizing Committee, we would like to welcome you to the fourth edition of the IEEE Vehicular Networking Conference in Seoul, Korea. IEEE VNC is a unique conference sponsored by both IEEE Communications Society and Intelligent Transportation Systems Society. It brings together these distinct communities to facilitate learning and to benefit from each others’ experience in the respective fields. The organizing committee spent countless hours and worked diligently to make this conference possible and to put together a high-quality program. Producing a conference is always a team effort involving many volunteers, and we would like to thank the team that made IEEE VNC 2012 possible. In particular, we are greatly indebted to our Technical Program Committee co-chairs, Frank Kargl, Falko Dressler, Elmar Schoch, Jong-Moon Chung, and Giovanni Pau, as well as to their TPC members. The TPC co-chairs compiled a very interesting program with highly respected and distinguished invited speakers, and an excellent technical program. The conference received 78 submissions of which 25 were accepted for the main technical program. Ten submissions were accepted as work in progress for the poster session. Our TPC co-chairs collected over 250 reviews from reviewers from all parts of the world. We also would like to thank EDAS Conference Services, LLC, especially Alice Arapshian, for helping to produce the proceedings. The staff of IEEE, in particular Bruce Worthman and Deidre Zeigler, helped with handling the finances and with making logistics arrangements. We would like to thank them for their support. The organizing committee would like to acknowledge the generous financial support from Toyota InfoTechnology Center and KAIST IREC that helped us to keep the registration fees at a reasonable rate. Last but not least, we would like to take this opportunity to express our gratitude to the IEEE Communications Society and IEEE Intelligent Transportation Systems Society for their joint sponsorship of the conference. We hope that all attendees will enjoy the scientific and social program, as well as the beautiful city of Seoul. Welcome to IEEE VNC 2012! Onur Altintas, Wai Chen, Geert Heijenk, and Hyun Seo Oh VNC 2012 General Chairs

In recent years, the growing prevalence of social networks makes it possible to utilize human users as sensors to inspect city environment and human activities. Consequently, valuable insights can be gained by applying data mining techniques to the data generated through social networks. In this work, a practical approach to combine data mining techniques with statistical analysis is proposed to implement crowd sensing in a smart city. A case study to analyze the relationship between weather conditions and traffic congestion in Beijing based on tweets posted on Sina Weibo platform is presented to demonstrate the proposed approach. Following the steps of data pre-processing and topic determination, we applied Granger Causality Test to study the causal relationships between weather conditions, traffic congestion and human outdoor activity. The mediation analysis is also implemented to verify human outdoor activity as a mediator variable significantly carrying the influence of good weather to traffic congestion. The result demonstrates that outdoor activity serves as a mediator transmitting the effect of good weather on traffic congestion. In addition, the causes of negative emotion are also studied.

While Twitter and other Online Social Networks (OSNs) or microblogs are considered as a source of information for breaking news or uproarious and unexpected events, they could also be exploited as a dense worldwide sensors network for physical measurements. The corpus of geotagged posts from OSNs includes people’s feedbacks about a wide range of topics, with precise temporal and geographical metadata, that can be used as a support or an improvement to hardware sensors. For instance, if collocated people, independently and at the same time, write posts complaining about high temperatures, it could effectively denote a raise of heat in that place. In this paper, we explore the feasibility to use a geographical search on social networks, that is, a geosocial search, about air pollution related posts, as effective air impureness measurements. We evaluate our assumption in large cities over three continents of the planet, where a minimum increment about the number of air pollution related posts in an area, indeed corresponds to a raise of minimum pollution values in such area. Such a correlation can be exploited to integrate and extend existing air pollution monitoring networks. At the end of the manuscript we propose to further employ the time series of posts returned by the geosocial search to predict next pollution values.

One of the main global challenges to cope with for a sustainable development is transport and mobility. They are undisputed key issues of modern life affecting people's well-being and quality of life, which are significantly impacting the environment. In this scenario, innovative self-driving car technologies and electric solutions, emerging sensing technologies, and interconnected infrastructure can lead to more efficient transport systems and innovative mobility services, keeping into account the urgent need to foster a sustainable development. This workshop aims to gather practitioners with different background and different perspective from both Academia and Industry to further the knowledge in the area of emerging smart technologies and infrastructures for Smart Mobility and Sustainability.

Mobility and ambient conditions are key factors in urban environments, affecting well-being and quality of life. In this context, sensors, smart mobility, networks, connectivity can play a significant and strategic role, being exploited with the aim of improving data and information available to public administration and to each citizen. In this way, they can be supported in having more sustainable and aware behaviours and in getting useful information and services, improving their daily activities. In this paper, we present a prototype of smart bike eco-system, designed with the aim of collecting, aggregating and sharing data about air pollution and about the urban environment, which can be exploited in a smart mobility context thanks to sensor and vehicular networks.

This paper makes the case for the use of blockchains in emerging intelligent transportation systems applications. Specifically, we argue for the use of blockchains to settle contracts and transactions in a variety of intelligent transportation scenarios. We argue that mainstream blockchains such as Ethereum have the foundations to sustain transactions with fine tunable granularity at large scale and in a near-realtime manner. The paper analyzes the refueling scenario for autonomous electric vehicles and proposes an algorithm to guarantee the execution of energy recharges.

In recent years, the growing prevalence of social networks makes it possible to utilize human users as sensors to inspect city environment and human activities. Consequently, valuable insights can be gained by applying data mining techniques to the data generated through social networks. In this work, a practical approach to combine data mining techniques with statistical analysis is proposed to implement crowd sensing in a smart city. A case study to analyze the relationship between weather conditions and traffic congestion in Beijing based on tweets posted on Sina Weibo platform is presented to demonstrate the proposed approach. Following the steps of raw dataset pre-processing, target dataset processing and statistical data analysis, analytic corpus containing tweets related to different weather conditions, traffic congestion and human outdoor activity is selected to test causal relationships by Granger Causality Test. The mediation analysis is also implemented to verify human outdoor activity as a mediator variable significantly carrying the influence of good weather to traffic congestion. The result demonstrates that outdoor activity serves as a mediator transmitting the effect of good weather on traffic congestion.

Connected vehicles and driverless cars are bringing an end to road transportation as we know it today. Autonomous cars will gain access to other vehicles' sensors; advanced navigation systems will enable greener and more efficient driving; and cars will form dynamic clouds, enabling a new generation of on-demand services in the fashion of today's cloud computing. Here, the author takes a glimpse at the road ahead. © 1997-2012 IEEE.

The notion of edge computing has gained much attraction in recent years as an enabling technology for smart city and internet of things applications. In this paper we report the system challenges and solutions encountered when designing and deploying the Macao Polytechnic Institute Smart City sensing system. A small fleet that serves as proof-of-concept for a country wide urban sensing system in Macao, S.A.R. We focus our attention on how a careful system design can ensure smooth operations and mitigate the natural tension between fleet owners and smart city operators. The first are keen to maximize the fleet operations and reduce the downtime, the later are interested in using the fleets to harvest high-quality and fine granularity sensor data. In designing the Macao Polytechnic Institute vehicular cloud we approached the design constraints and proposed system solutions to minimize the impact of the sensing platform on the fleet operations.

In the last several years the awareness about pollution levels and other natural hazards has risen significantly. Millions of citizens globally pay daily attention to air quality and other factors such as for instance UV index and pollens. This new need has been so far met by a plethora of smartphone applications that leverage data collected by the city-operated stations or, in some cases, community-based stations located at the user premises. In this work we exploit recent advances in micro-controllers and sensing technologies to design and implement a personal pollution awareness system tiny enough to be embedded into user accessories. In particular, we will introduce the concept and the architecture of our prototype and show the preliminary results we collected using this prototype.

Vehicles provide an ideal platforms for a plethora of emerging applications such as networked gaming, multimedia content delivery and urban sensing. Cars have no power constraints and they can be instrumented with high end computational units and graphic devices. The deployment at scale of urban vehicular systems, however, requires a careful design able to consider challenges across several domains. Vehicular systems are arguably a prominent example of cyber-physical systems. The development of such systems requires a truly multidisciplinary approach and a close integration between the application, communication, and physical domains. Hardware and software mounted on vehicles will face a harsh physical and communication environment that will greatly affect all the system components. In this paper we report on the challenges and opportunities for multimedia vehicular urban sensing systems based on our field experiences in Macao (China) and Los Angels (USA). We designed and built the components for a pollution monitoring system able to support closed-loop optimization between pollution and traffic management. Our initial set of prototype vehicles are now running in the city of Macao and they are measuring the air parameters as well as the urban traffic. The paper aims at exposing some of the issues encountered, outlining the problems of a city wide deployment, and augmenting our in-field experience with the results from large scale simulation studies. © 2012 Elsevier B.V.

The need for Internet access from moving vehicles has been steadily increasing in the past few years. Solutions that rely on cellular connectivity are becoming impractical to deploy due to technical and economic reasons. Car-Fi proposes an approach that leverages existing home Wi-Fi access points configured in dual-access mode, in order to offload all data traffic from the congested and expensive cellular infrastructure to whatever Wi-Fi network is available. Thanks to an improved scanning algorithm and numerous optimizations to the connection setup, Car-Fi makes downloading large amounts of data from a moving car feasible.

International audience; This paper proposes Navigo, a location based packet forwarding mechanism for vehicular Named Data Networking (NDN). Navigo takes a radically new approach to address the challenges of frequent connectivity disruptions and sudden network changes in a vehicle network. Instead of forwarding packets to a specific moving car, Navigo aims to fetch specific pieces of data from multiple potential carriers of the data. The design provides (1) a mechanism to bind NDN data names to the producers' geographic area(s); (2) an algorithm to guide Interests towards data producers using a specialized shortest path over the road topology; and (3) an adaptive discovery and selection mechanism that can identify the best data source across multiple geographic areas, as well as quickly react to changes in the V2X network.

International audience; Traditionally, the vehicle has been the extension of the man's ambulatory system, docile to the driver's commands. Recent advances in communications, controls and embedded systems have changed this model, paving the way to the Intelligent Vehicle Grid. The car is now a formidable sensor platform, absorbing information from the environment (and from other cars) and feeding it to drivers and infrastructure to assist in safe navigation, pollution control and traffic management. The next step in this evolution is just around the corner: the Internet of Autonomous Vehicles. Pioneered by the Google car, the Internet of Vehicles will be a distributed transport fabric capable to make its own decisions about driving customers to their destinations. Like other important instantiations of the Internet of Things (e.g., the smart building), the Internet of Vehicles will have communications, storage, intelligence, and learning capabilities to anticipate the customers' intentions. The concept that will help transition to the Internet of Vehicles is the Vehicular Cloud, the equivalent of Internet cloud for vehicles, providing all the services required by the autonomous vehicles. In this article, we discuss the evolution from Intelligent Vehicle Grid to Autonomous, Internet-connected Vehicles, and Vehicular Cloud.

Existing mobile devices have the capability to use multiple network technologies simultaneously to help increase performance; but they rarely, if at all, effectively use these technologies in parallel. We first present empirical data to help understand the mobile environment when three heterogeneous networks are available to the mobile device (i.e., a WiFi network, WiMax network, and an Iridium satellite network). We then propose a reliable, multi-path protocol called Multi-Path TCP with Network Coding (MPTCP/NC) that utilizes each of these networks in parallel. An analytical model is developed and a mean-field approximation is derived that gives an estimate of the protocol's achievable throughput. Finally, a comparison between MPTCP and MPTCP/NC is presented using both the empirical data and mean-field approximation. Our results show that network coding can provide users in mobile environments a higher quality of service by enabling the use of multiple network technologies and the capability to overcome packet losses due to lossy, wireless network connections., Accepted to VTC2013-Fall, 5 Pages, 6 Figures

This paper presents the first prototype of Multipath Ad-hoc Data Network (MADN) a clean slate protocol for ad-hoc wireless content distribution. Inspired by the recent advances on Information Centric Networking (ICN), MADN is namely a pull-based protocol that emphasizes on seamless route redundancy and multi-path data delivery. It is complementary to the former IP protocol and therefore does not implement primitives for machine-to-machine communication. In consideration of targeting specifically the wireless medium, it uses rateless encoded data packets to counterbalance packet loss and to benefit from multi-source data distribution. A major difference between MADN and previous works is the use of the BlooGo algorithm in place of the conventional routing protocols - e.g. random walks, landmarks or coordinate spaces. The main advantages of using BlooGo is that it delivers the packets in considerably less hops while it maintains alternative routes open as backup of the shortest ones. This paper serves two aims, firstly it proposes a new protocol for multipath content distribution in ad-hoc environments, secondly it presents its architecture and how this interfaces with the final applications. Ultimately, the implementation is intentionally kept modular in order to facilitate deploying and evaluation of new solutions and new configurations - e.g. different caching algorithms or different types of Erasure Codes - without major refactoring of the codebase. © 2013 IEEE.

Cloud computing allows user to access remote hardware, data and software through the network. However, many of these resources today are found on mobiles. For example, modern vehicles provide powerful platforms for computation, data delivery, storage, and sensing. This paper introduces the notion of Mobile Cloud computing to tap mobile resources. As an example, we describe the Pies-on-Wheels service, a Vehicular Cloud service that delivers images on demand to citizens by using vehicles' on board cameras. A server (eg taxi dispatcher or Navigator Server) accepts requests from members and assigns the photo clicking task to vehicles close to the target. The feasibility of the Pies-on-Wheels service is demonstrated in a San Francisco scenario using published taxicab routes. © 2013 IEEE.

Social network companies maintain complete visibil- ity and ownership of the data they store. However users should be able to maintain full control over their own content. For this purpose, we propose WARP, an architecture based upon Information-Centric Networking (ICN) designs, which expands the scope of the ICN architecture beyond media distribution, to provide data control in social networks. The benefit of our solution lies in the lightweight nature of the protocol and in its layered design. With WARP, data distribution and access policies are enforced on the user side. Data can still be replicated in an ICN fashion but we introduce control channels, named thread updates, which ensures that the access to the data is always updated to the latest control policy. WARP decentralizes the social network but still offers APIs so that social network providers can build products and business models on top of WARP. Social applications run directly on the user's device and store their data on the user's butler that takes care of encryption and distribution. Moreover, users can still rely on third parties to have high- availability without renouncing their privacy. I. INTRODUCTION Online social networks (OSNs) such as Facebook, Twitter, Google+, Myspace, LinkedIn, etc. have become irreplaceable to form virtual communities. The data shared over an OSN can be very personal and demand immediacy from the provider. As a consequence, OSNs gather huge amount of data about their users, and are now the real custodians of people's identity. Some OSNs even allow third party's software to use this knowledge. Social data can also be used to infer people's interests in order to win their attention and deliver messages more effectively, such as advertisements. The OSN platform can also be used by governments and legal agencies to monitor the user's activities. This sharing of the users' data may happen without the explicit consent of the user. Recent research efforts (25), (23), (27), (9), as well as com- mercial initiatives (say, Tent.io), have proposed to decentralize the social network so that users can maintain control over their data. Concurrently, the research community has developed new ideas for an Internet architecture that can better serve the needs of users and developers. In particular, Information Centric Networking (ICN) architectures focus on connecting users to data instead of setting up connections between machines. It is our belief that ICN architectures are now mature enough to overcome the network issues that distributed social networking has faced so far. Therefore, we propose a solution that imple- ments all the functionality common to social networks while leaving the users in full control of their data. Furthermore, our solution is compatible with the value add of current OSN providers. In this paper we present the WARP framework, that is: an architecture that allows users to share data, potentially over the infrastructure of an OSN provider, but which prevents the OSN provider to access to the user's data without the explicit consent of the user.

MoViT is a distributed software suite for the emulation of mobile wireless networks. MoViT provides researchers and developers with a virtualized environment for developing and testing mobile applications and protocols for any hardware and software platform that can be virtualized. The distributed nature of MoViT allows for the emulation of mobile networks of arbitrary size. Additionally, the network connectivity is shaped transparently such that the connectivity observed by each virtual node resembles that of a physical mobile network. In this paper we present the MoViT architecture, the models used to emulate the wireless channel, the details of our initial implementation and, finally, the results of our evaluation regarding the scalability, realism, and versatility of MoViT. © 2012 ACM.

Clock synchronization is particularly challenging in resource constrained networks. This paper presents an accurate, coherent and bandwidth efficient synchronization scheme called TurboSync. Unlike traditional solutions that synchronize pairs of nodes, TurboSync is able to synchronize entire node clusters. TurboSync relies on principal component analysis with missing data. Packets are broadcasted on the medium and their capture times at each node side are used to compute the clock conversion parameters. To have a complete and usable set of capture times for each broadcast, we propose to fill out the missing packet timestamps at the transmitters' side using an inference mechanism. TurboSync synchronizes all the clocks in the cluster at a time which leads to coherent clock conversion between nodes. Our performance results show better accuracy compared to the RBS protocol. © 2011 IEEE.

In this paper, we propose a simple and effective method to extend digital maps with the location and timing of stop-signs and traffic lights in a city, given GPS traces collected by on-road vehicles. Our system finds the location and timing of traffic lights and stop-signs using a small number of traces per road segment. We developed and evaluated the system by applying it to two sets of GPS traces -open street map, a multicity, publicly available database of GPS traces, and a set of traces collected in west Los Angeles. Evaluation results show that our system can estimate the location of stop-signs with as little as 5 traversal per road segment and the location/timing of traffic lights with as little as 7 traversals, with more than 90% accuracy. © 2010 IEEE.

Vehicular networks are on the fast track to become a reality either through a car manufacturer that introduces a communication device in the car electronics or through an aftermarket vendor such a GPS navigator or a in-vehicle entertainment system. This paper introduces VERGILIUS a nouvelle urban mobility and propagation toolbox designed to streamline the mobility trace generation and path loss computation in vehicular network studies. The aim of VERGILIUS is to enable a whole new level of simulation through the introduction of Urban Maps, finely tunable motion patterns, and detailed trace analysis.

The investigation around the use of peer-to-peer in IPTV environments goes on. The debate about the best compromise between the cost reduction offered by the peer-to-peer (P2P) approach and the quality requirements by the mass market is still open. Though some successful protocols are already worldwide used, there are still issues and optimization problems to solve. The main contribution of this work has been the deployment on PlanetLab (Plab) of a large testbed in order to investigate the performance of [P2P client - streaming player] systems in static and dynamic overlays: the goal was to recreate a real IPTV-like heterogeneous scenario with home users enjoying the same stream and cooperating via P2P. IPTV needs bandwidth and computational resources that single peers often struggle to provide. We chose the SopCast client for our experiments, mainly because of its popularity and its flexibility. Although SopCast analysis was not our main research purpose, we are able to point out some of its characteristics by observing its behavior in large and dynamic overlay, with different churn patterns (i.e. zapping channel behaviors). ©2009 IEEE.

The Internet is incontrovertibly a great success that has changed our social and economic world. Today, over one billion users access the Internet on regular basis, more than 100 million users have downloaded at least one (multi) media file, and over 47 million of them do so regularly, searching in more than 160 exabytes of content. The content is expected to rise to more than 990 exabytes before 2012, fueled mainly by the users themselves [1]. It is envisaged that in the near- to mid-term future, mobile Internet will provide the means to share and distribute (new) multimedia content and services with superior quality and striking flexibility, in a trusted and personalized way, improving citizens? quality of life, working conditions, edutainment, and safety.

Multicast streaming is gaining increasing importance in wireless ad hoc networks, in part because ad hoc scenarios often include team activities and the requirement for distribution of audio, video and situation awareness to the members. At the network level, techniques for routing the multimedia streams are quite mature. Much more challenging is the allocation of resources, the fair sharing among streams and the control of congestion. While in rate adaptive UNICAST streams congestion control and fair sharing are accomplished with end-to-end feedback techniques inspired to TCP, the feedback does not scale well in MULTICAST. In fact, it leads to the well knows ACK/NAK "implosion" problem and unfair penalties for heterogeneous receivers. These limitations can be overcome using backpressure from congestion points to the sources - but this approach suffers of latency and cannot rapidly adjust to changes in traffic. Another solution is multilayer adaptive coding. Namely, the encoding adaptation is done locally by dropping layers. It does not require end-to-end feedback nor changes in input rates. Multi-resolution codes are now becoming attractive due to the progress in technology; we expect these to become the prevalent techniques in large scale media distribution. One issue, however, that still remains to be resolved is the fair sharing among competing multicast streams. In this paper we address the congestion control AND fair sharing in a multilayer multicast scenario. We show that lack of proper fairness provisions in the "local adjustments" can lead to serious capture situations, especially in heterogeneous traffic mixes (e.g. voice and video). We then propose a FAIR local adjustment that targets a fair dropping of packets in each interference domain. We show that the scheme can be interpreted as a distributed implementation of a utility function minimization, where the utility is the packet loss subject to fairness bounds across flows. This formulation guarantees stability and convergence of the distributed algorithm. The main contributions of this paper are the low overhead design of the local fairness enforcement algorithm, the utility function framework and the demonstration of convergence via simulation in representative scenarios. Copyright 2008 ACM.

C-VeT's backbone is based on the UCLA's IEEE 802.11 campus-wide wireless infrastructure and is complemented by a wireless mesh provided by MobiMesh. The nodes participating in the mesh are installed in strategic campus location and perform packet routing as well as serve as access points for the mobile nodes. The mesh core network is deployed using IEEE 802.11a interfaces at 5.9 GHz and directional antennas while the access service is offered using IEEE 802.11g interfaces in the 2.4 GHz band. The network management and monitoring infrastructure has been deployed using a wide area wireless network technology in the ISM band of 900 MHz red links. The 900 MHz digital radio, provides enough bandwidth to perform realtime monitoring of the vehicular network and maintenance of the network nodes. The 900 MHz wireless infrastructure has been laid down to guarantee an independent channel to be used for network management and monitoring operations without interferences with on going experiments.

In an urban environment, vehicles can opportunistically exploit infrastructure through open Access Points (APs) to efficiently communicate with other vehicles. This is to avoid long wireless ad hoc paths, and to alleviate congestion in the wireless grid. Analytic and simulation models are used to optimize the communications and networking strategies. For realistic results, one important challenge is the accurate representation of traffic mobility patterns. In this paper we introduce realistic vehicular mobility traces of downtown Portland, Oregon, obtained fromextremely detailed large scale traffic simulations performed at the Los Alamos National Laboratories (LANL). To the best of our knowledge, these are among the most accurate synthetic motion traces available for study, with the exception of actual car trace measurements. The new mobility model is used to evaluate AODV [1] in flat and opportunistic infrastructure routing. To assess the importance of a realistic mobility model for this evaluation, we compare these results with those obtained with CORSIM [2] traces. The paper makes the following contributions: (a) introduction of efficient, opportunistic strategies for extending the AP infrastructure to use vehicle to vehicle paths, and (b) assessment of different mobility models - CORSIM traces and LANL's realistic vehicular traces - in the modeling of different routing strategies. Copyright 2007 ACM.

In [1] we show how vehicles can opportunistically exploit infrastructure through open Access Points (APs) to efficiently communicate with other vehicles. We also highlight the importance of the use of a correct mobility model, since the advantages that may derive from the use of an infrastructure may not be appreciated because of a lack of accuracy. We continue our study based on realistic vehicular mobility traces of downtown Portland, Oregon, obtained from extremely detailed large scale traffic simulations performed at the Los Alamos National Laboratories (LANL). This mobility model is used to evaluate both flat and opportunistic infrastructure routing. We here build upon [1] and extend that work to: (a) assess the impact of a range of mobility models on network performance and; (b) discuss the performance trend we may expect during the day, as urban mobility patterns change. We here compare results obtained with CORSIM [2] traces and Random Waypoint (RWP) [3] to the results obtained with realistic mobility traces. ©2007 IEEE.

Fast-FMS is a new network protocol designed to support fast and effective multimedia delivery in 3G networks. In particular, Fast-FMS provides a reliable session between two mobile customers that want to transmit multimedia and data while on a voice conversation. The protocol leverages the multi-RAB feature of 2.5+ cellular networks to provide a new almost-real-time class of services that fill the gap between the costly circuit-switched video-call service and the basic services based on MMS. 1. Fast-FMS Description

Increasing need for people to be "connected"; while at the same time remain as mobile as ever poses several interesting issues in wireless networks. It is conceivable in the near-future that wireless "hotspots" experience flash crowds-like traffic arrival pattern. A common phenomena in the Internet today characterized by sudden and unpredicted increase in popularity of on-line content. In this paper, we propose SPAWN, a cooperative strategy for content delivery and sharing in future vehicular networks. We study the issues involved in using such a strategy from the standpoint of vehicular ad-hoc networks. In particular, we show that not only content server but also wireless access network load reduction is critical. We propose a "communication efficient" swarming protocol which uses a gossip mechanism that leverages the inherent broadcast nature of the wireless medium, and a piece-selection strategy that takes proximity into account in decisions to exchange pieces. We show through simulation that gossip incorporates location-awareness into peer selection, while incurring low messaging overhead, and consequently enhancing the swarming protocol performance. We develop an analytical model to characterize the performance of SPAWN. © 2004 IEEE.

The IEEE802.11x based wireless LAN technologies are leading the indoor Internet distribution in education, business and home environments. They are usually deployed as wireless extension of a broadband access to the network (i.e. DSL, cable modem, etc). These technologies are based on CSMA/CA media access with a positive MAC layer acknowledgement and a retransmission mechanism that aids noisy channel propagation condition and eventual undetected collisions. While TCP traffic benefits from a layer 2 retransmission policy the multimedia traffic experiences large delays and jitter resulting in a poor user experience. In this paper we satisfy the emerging user need of a MAC layer Quality of Service (QoS) support by taking advantage from layers 4-7 information. We believe the concepts and the architectural design presented are suitable to enhance QoS support in wireless technologies. © 2003 IEEE.

Mobile peer-to-peer (P2P) systems have recently got in the limelight of the research community that is striving to build efficient and effective mobile content addressable networks. Along this line of research, we propose a new peer-to-peer file sharing protocol suited to mobile ad hoc networks (MANET). The main ingredients of our protocol are network coding and mobility assisted data propagation, i.e., single-hop communication. We argue that network coding in combination with single-hop communication allows P2P file sharing systems in MANET to operate in a more efficient manner and helps the systems to deal with typical MANET issues such as dynamic topology and intermittent connectivity as well as various other issues that have been disregarded in previous MANET P2P researches such as addressing, node/user density, non-cooperativeness, and unreliable channel. Via simulation, we show that our P2P protocol based on network coding and single-hop communication allows shorter file downloading delays compared to an existing MANET P2P protocol. © 2008 KICS.

Future vehicular networks are expected to deploy shortrange communication technology for inter-vehicle communication. In addition to vehicle-to-vehicle communication, users will be interested in accessing the multimedia-rich Internet from within the vehicular network. This motivates a compelling application of Co-operative Networking in the Vehicular Ad-Hoc network where the Ad Hoc network extends and complements the Internet. The broadcast nature of the wireless medium drives us to explore different design paradigms from the ones used in typical wired settings. A new paradigm in content delivery on the Internet using peer-peer swarming protocols is emerging [1, 2]. We propose SPAWN, a simple cooperative strategy for content delivery in future vehicular networks. We study the issues involved in using such a strategy from the standpoint of Vehicular Ad-Hoc networks. Several enhancements to a popular swarming protocol (BitTorrent) are discussed including a gossip mechanism that leverages the inherent broadcast nature of the wireless medium, and a piece-selection strategy that uses proximity to exchange pieces quicker. Preliminary results show that SPAWN increases the perceived performance of the network, resulting in faster downloads for popular files.

Next generation networks with large bandwidth and long delay pose a major challenge to TCP performance, especially during the startup period. In this paper we evaluate the performance of TCP Reno/Newreno, Vegas and Hoe's modification in large bandwidth delay networks. We propose a modified Slow-start mechanism, called Adaptive Start (Astart), to improve the startup performance in such networks. When a connection initially begins or re-starts after a coarse timeout, Astart adaptively and repeatedly resets the Slow-start Threshold (ssthresh) based on an eligible sending rate estimation mechanism proposed in TCP Westwood. By adapting to network conditions during the startup phase, a sender is able to grow the congestion window (cwnd) fast without incurring risk of buffer overflow and multiple losses. Simulation experiments show that Astart can significantly improve the link utilization under various bandwidth, buffer size and round-trip propagation times. The method avoids both under-utilization due to premature Slow-start termination, as well as multiple losses due to initially setting ssthresh too high, or increasing cwnd too fast. Experiments also show that Astart achieves good fairness and friendliness toward TCP NewReno. Lab measurements using a FreeBSD Astart implementation are also reported in this paper, providing further evidence of the gains achievable via Astart.