Construction of a real vehicular delay-tolerant network testbed

Vehicular Delay-Tolerant Networks (VDTNs) appear as innovative network architecture, able to outline communication challenges caused by issues like variable delays, disruption and intermittent connectivity once that it utilizes the store-carry-and-forward method to allow that in-transit messages (called bundles) can be delivered to the destination by hopping over the mobile vehicles even that an end-to-end path does not exist. Since messages are stored persistently in a buffer and forward to the next hop, a new communication infrastructure is created allowing low-cost asynchronous opportunistic communication under the most critical situations like variable delays and bandwidth constraints. VDTN introduces a layered architecture, acting as an overlay network over the link layer, aggregating incoming IP packets in data bundles (large IP packets), using out-of-band signaling, based on the separation of the control plane and planes. This dissertation presents and evaluates the performance of a real VDTN testbed, demonstrating the real applicability of this new vehicular communication approach. It includes an embedded VDTN testbed created to evaluate safety systems in a real-world scenario. It was used cars with laptops to realize terminal and relay nodes. A real testbed is very important because some complex issues presented in vehicular communication systems can be treated with more realism in real-world environments than in a laboratory environment. The experiments were performed on the internal streets of Brazilian Fiat Automobile manufacturing plant. Performance measurements and analysis were also conduct to verify the efficiency of the system. The results obtained show that safety applications and services can be executed with the actual proposal VDTN architecture in several environments, although notable interference as fading and characteristics of the radio channel, require the use of more modern, appropriate and robust technologies. Thus, the real deployment of VDTNs confirms that VDTNs can be seen as a very promising technology for vehicular communications.Fundação para a Ciência e a Tecnologia (FCT

Rover: Poor (but Elegant) Man’s Testbed

International audienceThis paper presents the OpenVisualizer Rover testbed, a simple, easy-to-deploy and cheap testbed for the Internet of Things (IoT). The OpenWSN project provides a free and open-source implementation of a standards-compliant protocol stack for the IoT, as well as all the necessary network management and debugging tools. The network management software, OpenVisualizer, is portable across popular operating systems, and connects the OpenWSN low-power wireless mesh network to the Internet. In the current setup, motes are connected to the USB ports of the computer the OpenVisualizer runs on. The OpenVisualizer monitors the internal state of those motes, which it presents through a web interface. Rover extends the OpenVisualizer by allowing motes plugged into different computers to remotely connect to it. Once connected, a user monitors and manages the motes exactly as if they were connected locally. This offers endless experimentation possibilities, as the resulting testbed can be quickly (re)deployed in realistic environments. An example Rover testbed has been deployed at the Cisco Paris Innovation and Research Lab. This paper discusses the Rover architecture, the deployment, and the experimental research done with it

A Roadmap for Benchmarking in Wireless Networks

Experimentation is evolving as a viable and realistic performance analysis approach in wireless networking research. Realism is provisioned by deploying real software (network stack, drivers, OS), and hardware (wireless cards, network equipment, etc.) in the actual physical environment. However, the experimenter is more likely to be dogged by tricky issues because of calibration problems and bugs in the software/hardware tools. This, coupled with difficulty of dealing with multitude of hardware/software parameters and unpredictable characteristics of the wireless channel in the wild, poses significant challenges in the way of experiment repeatability and reproducibility. Furthermore, experimentation has been impeded by the lack of standard definitions, measurement methodologies and full disclosure reports that are particularly important to understand the suitability of protocols and services to emerging wireless application scenarios. Lack of tools to manage large number experiment runs, deal with huge amount of measurement data and facilitate peer-verifiable analysis further complicates the process. In this paper, we present a holistic view of benchmarking in wireless networks and formulate a procedure complemented by step-by-step case study to help drive future efforts on benchmarking in wireless network applications and protocols

A review of cyber-ranges and test-beds:current and future trends

Cyber situational awareness has been proven to be of value in forming a comprehensive understanding of threats and vulnerabilities within organisations, as the degree of exposure is governed by the prevailing levels of cyber-hygiene and established processes. A more accurate assessment of the security provision informs on the most vulnerable environments that necessitate more diligent management. The rapid proliferation in the automation of cyber-attacks is reducing the gap between information and operational technologies and the need to review the current levels of robustness against new sophisticated cyber-attacks, trends, technologies and mitigation countermeasures has become pressing. A deeper characterisation is also the basis with which to predict future vulnerabilities in turn guiding the most appropriate deployment technologies. Thus, refreshing established practices and the scope of the training to support the decision making of users and operators. The foundation of the training provision is the use of Cyber-Ranges (CRs) and Test-Beds (TBs), platforms/tools that help inculcate a deeper understanding of the evolution of an attack and the methodology to deploy the most impactful countermeasures to arrest breaches. In this paper, an evaluation of documented CR and TB platforms is evaluated. CRs and TBs are segmented by type, technology, threat scenarios, applications and the scope of attainable training. To enrich the analysis of documented CR and TB research and cap the study, a taxonomy is developed to provide a broader comprehension of the future of CRs and TBs. The taxonomy elaborates on the CRs/TBs dimensions, as well as, highlighting a diminishing differentiation between application areas

A stepping stone perspective to detection of network threats

Current computing trends such as cloud computing, file sharing and social networking promote collaboration and allow greater mobility for users.Nevertheless, these computing trends increase the vulnerability of networks to security threats and challenge network resources.An ingenious technique employed by attackers for retaining anonymity is by exploiting intermediary host computers or stepping stones to instigate attacks on other computers.This paper explores novel application of the stepping stone detection concept in addressing network threats such as spams, backdoors, proxy server intrusions and denial of service attacks.Preliminary stepping stone detection models for each security threat will be constructed and the potential detection process is delineated.These preliminary concepts and models may prove useful for further optimization of network security in conjunction with other conventional detection techniques

An Adaptive Packet Aggregation Algorithm (AAM) for Wireless Networks

Packet aggregation algorithms are used to improve the throughput performance by combining a number of packets into a single transmission unit in order to reduce the overhead associated with each transmission within a packet-based communications network. However, the throughput improvement is also accompanied by a delay increase. The biggest drawback of a significant number of the proposed packet aggregation algorithms is that they tend to only optimize a single metric, i.e. either to maximize throughput or to minimize delay. They do not permit an optimal trade-off between maximizing throughput and minimizing delay. Therefore, these algorithms cannot achieve the optimal network performance for mixed traffic loads containing a number of different types of applications which may have very different network performance requirements. In this thesis an adaptive packet aggregation algorithm called the Adaptive Aggregation Mechanism (AAM) is proposed which achieves an aggregation trade-off in terms of realizing the largest average throughput with the smallest average delay compared to a number of other popular aggregation algorithms under saturation conditions in wireless networks. The AAM algorithm is the first packet aggregation algorithm that employs an adaptive selection window mechanism where the selection window size is adaptively adjusted in order to respond to the varying nature of both the packet size and packet rate. This algorithm is essentially a feedback control system incorporating a hybrid selection strategy for selecting the packets. Simulation results demonstrate that the proposed algorithm can (a) achieve a large number of sub-packets per aggregate packet for a given delay and (b) significantly improve the performance in terms of the aggregation trade-off for different traffic loads. Furthermore, the AAM algorithm is a robust algorithm as it can significantly improve the performance in terms of the average throughput in error-prone wireless networks