In disruption-tolerant networking (DTN), data is transmitted in a store-carry-forward fashion from network node to network node. In this paper, we present an open source DTN implementation, called DTN7, of the recently released Bundle Protocol Version 7 (draft version 13). DTN7 is written in Go and provides features like memory safety and concurrent execution. With its modular design and interchangeable components, DTN7 facilitates DTN research and application development. Furthermore, we present results of a comparative experimental evaluation of DTN7 and other DTN systems including Serval, IBR-DTN, and Forban. Our results indicate that DTN7 is a flexible and efficient open-source multi-platform implementation of the most recent Bundle Protocol Version 7.
Content-centric networking (CCN) introduces a paradigm shift from a host centric to an information centric communication model for future Internet architectures. It supports the retrieval of a particular content regardless of the physical location of the content. Content caching and content delivery networks are the most popular approaches to deal with the inherent issues of content delivery on the Internet that are caused by its design. Moreover, intermittently connected mobile environments or disruptive networks present a significant challenge to CCN deployment. In this paper, we consider th…
Disruption Tolerant Networks (DTNs) are employed in applications where the network is likely to be disrupted due to environmental conditions or where the network topology makes it impossible to find a direct route from the sender to the receiver. Underwater networks typically use acoustic waves for transmitting data. However, these waves are susceptible to interference from sources of noise such as the wake from ships, sounds from snapping shrimp, and collisions from acoustic waves generated by other nodes. DTNs are good candidates for situations where successfully delivering the message is mo…
In Software-Defined Networking (SDN), network applications use the logically centralized network view provided by the controller to remotely orchestrate the network switches. To avoid the controller being a single point of failure, traditional fault-tolerance techniques are employed to guarantee availability, a fundamental requirement in production environments. Unfortunately, these techniques fall short of ensuring correct network behaviour under controller failures. The problem of these techniques is that they deal with only part of the problem: guaranteeing that application and controller s…
The objective of this analysis was to simulate the performance of three different ad-hoc protocols for disruption-tolerant networking (DTN) - i.e. the transfer of information through a network of nodes in contexts prone to signal interruption/signal degradation - and to perform a trade-off analysis that will yield a recommendation of the best course of action (COA) for a user of a space-based network to employ. This is important for space-based networks in particular since transmitting information over long distances - e.g. from directly from the initial node to the destination node - will res…
Delay Tolerant Networking (DTN) has been proposed as a new architecture to provide efficient store-carry-and-forward data transport in satellite networks. Since these networks relay on scheduled contact plans, the Contact Graph Routing (CGR) algorithm can be used to optimize routing and data delivery performance. However, in spite of the various improvements that have been made to CGR, there have been no significant proposals to prioritize traffic with different quality of service requirements. In this work we propose adaptations to CGR that allow performance improvements when sending traffic …
For energy-harvesting sensor nodes, rechargeable batteries play a critical role in sensing and transmissions. By coupling two simple Markovian queue models in a delay-tolerant networking setting, we consider the problem of battery sizing for these sensor nodes to operate effectively: given the intended energy depletion and overflow probabilities, how to decide the minimal battery capacity that is required to ensure opportunistic data exchange despite the inherent intermittency of renewable energy generation.
University of Chinese Academy of Sciences（中国科学院大学）；Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences（中国科学院空间应用工程与技术中心）
In recent years, with the large-scale deployment of space spacecraft entities and the increase of satellite onboard capabilities, delay/disruption tolerant network (DTN) emerged as a more robust communication protocol than TCP/IP in the case of excessive network dynamics. DTN node buffer management is still an active area of research, as the current implementation of the DTN core protocol still relies on the assumption that there is always enough memory available in different network nodes to store and forward bundles. In addition, the classical queuing theory does not apply to the dynamic man…
This paper presents a novel storage aware routing (STAR) protocol designed to provide a general networking solution over a broad range of wired and wireless usage scenarios. STAR enables routing policies which adapt seamlessly from a well-connected wired network to a disconnected wireless network. STAR uses a 2-Dimensional routing metric composed of a short and a long term route cost and storage availability on downstream routers to make store or forward routing decisions. Temporary in-network storage is preferred over forwarding along a path that is slower than average and opportunistic trans…
Delay-Tolerant Networks (DTN) enable store-carry-and-forward data transmission in networks challenged by frequent disruptions and high latency. Existing classification distinguishes between scheduled and probabilistic DTNs, for which specific routing solutions have been developed. In this paper, we uncover a gap in-between where uncertain contact plans can be exploited to enhance data delivery in many practical scenarios described by probabilistic schedules available a priori. Routing under uncertain contact plans (RUCoP) is next formulated as a multiple-copy Markov Decision Process and then e…
In order to cope with the explosive growth of data traffic which is associated with a wide plethora of emerging applications and services that are expected to be used by both ordinary users and vertical industries, the congestion control mechanism is considered to be vital. In this paper, we proposed a congestion control mechanism that could function within the framework of Multi-Access Edge Computing (MEC). The proposed mechanism is aiming to make real-time decisions for selectively buffering traffic while taking network condition and Quality of Service (QoS) into consideration. In order to s…
Information-Centric Networking (ICN) introduces a paradigm shift from a host centric communication model for Future Internet architectures. It supports the retrieval of a particular content regardless of the physical location of the content. Emergency network in a disaster scenario or disruptive network presents a significant challenge to the ICN deployment. In this paper, we present a Content dIstribution and retrieval framework in disaster netwOrks for public pRotection (CIDOR) which exploits the design principle of the native CCN architecture in the native Delay Tolerant Networking (DTN) ar…
Congestion Aware Spray And Wait Protocol: A Congestion Control Mechanism For The Vehicular Delay Tolerant Network
在过去的几年里，车载自组织网络（VANET）已经成为一个重要的研究领域。为提高车辆网络排放系统的性能进行了大量研究。对VANET进行的进一步研究的一个结果是车辆延迟容忍网络（VDTN）。它是移动DTN的一种应用，其中节点使用存储-携带-转发方法在网络中中继消息。由于它的高移动性，它遭受频繁的断开连接，也在节点处，这导致消息丢弃的拥塞。为了最大限度地减少消息的下降率，从而优化消息传递的概率，使司机越来越多地了解道路的情况，我们提出了一种拥塞控制机制：拥塞感知喷射和等待（CASaW）协议在这项工作中，以优化消息传递到其目的地的速率，从而提高司机在车辆环境中的意识，从而提高道路安全。结果表明，我们的命题表现优于其他经典的VDTN协议的消息传递概率和丢包率的性能指标。我们使用虚拟网络环境（ONE）模拟器实现了经典的VDTN协议：PROPHET协议，Epidemic协议，MaxProp协议和Spray and Wait协议。仿真结果表明，我们提出的拥塞控制机制具有更好的性能，因为它保持了良好的消息传递率，以及最小化数据包丢失率，从而优化了消息到达目的地的机会，从而提高道路安全。
A number of geolocation-based Delay Tolerant Networking (DTN) routing protocols have been shown to perform well in selected simulation and mobility scenarios. However, the suitability of these mechanisms for vehicular networks utilizing widely-available inexpensive Global Positioning System (GPS) hardware has not been evaluated. We propose a novel geolocation-based routing primitive (Centroid Routing) that is resilient to the measurement errors commonly present in low-cost GPS devices. Using this notion of Centroids, we construct two novel routing protocols and evaluate their performance with …
Software-defined networking offers numerous benefits against the legacy networking systems through simplifying the process of network management and reducing the cost of network configuration. Currently, the management of failures in the data plane is limited to two mechanisms: proactive and reactive. Such failure recovery techniques are activated after occurrences of failures. Therefore, packet loss is highly likely to occur as a result of service disruption and unavailability. This issue is not only related to the slow speed of recovery mechanisms, but also the delay caused by the failure de…
A One-Hop Information Based Geographic Routing Protocol for Delay Tolerant MANETs
延迟和中断容忍网络（DTN）可能缺乏连续的网络连接。因此，DTN中的路由是一个挑战，因为它必须处理网络分区，长延迟和动态拓扑。与此同时，传统的移动自组织网络（MANET）的路由协议不能很好地工作，因为它的假设，大多数网络连接是可用的失败。在这篇文章中，提出了一个地理路由协议的MANNETWORK在延迟容忍的情况下，通过使用不超过一跳的信息。设计了一个效用函数来实现欠控制复制策略。为了减少消息泛滥所造成的开销，我们采用了一个标准来评估消息的冗余程度。因此，一个消息冗余处理机制被添加到我们的路由协议。大量的仿真结果表明，当节点移动速度较低时，该路由协议在引入可接受的网络开销率的同时，在投递率和平均跳数方面优于Epidemic、Spray and Wait、FirstContact等协议.
Many Internet of things (IoT) applications have been developed and implemented on unreliable wireless networks like the Delay tolerant network (DTN), however, efficient data transfer in DTN is still an important issue for the IoT applications. One of the application areas of DTN is Vehicular Delay Tolerant Network (VDTN) where the network faces communication disruption due to lack of end-to-end relay route. It is challenging as some of the nodes show selfish behavior to preserve their resources like memory, and energy level and become non-cooperative. In this article, an Honesty based Democrat…
The term Delay/Disruption-Tolerant Networks (DTN) invented to describe and cover all types of long-delay, disconnected, intermittently connected networks, where mobility and outages or scheduled contacts may be experienced. This environment is characterized by frequent network partitioning, intermittent connectivity, large or variable delay, asymmetric data rate, and low transmission reliability. There have been routing protocols developed in DTN. However, those routing algorithms are design based upon specific assumptions. The assumption makes existing algorithms suitable for specific environ…
Software-defined networking (SDN) enables advanced operation and management of network deployments through (virtually) centralised, programmable controllers, which deploy network functionality by installing rules in the flow tables of network switches. Although this is a powerful abstraction, buggy controller functionality could lead to severe service disruption and security loopholes, motivating the need for (semi-)automated tools to find, or even verify absence of, bugs. Model checking SDNs has been proposed in the literature, but none of the existing approaches can support dynamic network d…
The number of disasters has increased over the past decade where these calamities significantly affect the functionality of communication networks. In the context of 6G, airborne and spaceborne networks offer hope in disaster recovery to serve the underserved and to be resilient in calamities. Therefore, this paper surveys the state-of-the-art literature on post-disaster wireless communication networks and provides insights for the future establishment of such networks. In particular, we first give an overview of the works investigating the general procedures and strategies for counteracting a…
Consensus Protocols for Entanglement-Aware Scheduling in Distributed Quantum Neural Networks
Imperial College London（伦敦帝国理工学院）；Centre for Quantum Engineering, Science and Technology (QuEST), Imperial College London（伦敦帝国理工学院量子工程、科学与技术中心）；Brookhaven National Laboratory（布鲁克海文国家实验室）；Department of Electrical and Computer Engineering, American University of Beirut（贝鲁特美国大学电气与计算机工程系）
