Delay Tolerant Network Protocols Research Articles

Study to integrate Delay-Tolerant Network protocols in IoT LEO constellations for flood prevention

In the era of the Internet of Things (IoT) the development of Direct-to-Satellite IoT (DtS-IoT) applications are becoming increasingly relevant. These applications are based on enabling IoT devices to communicate directly with satellites. In this scenario, LEO satellites can provide global IoT service coverage, becoming essential to connect devices in remote areas. As an example, the deployment of NarrowBand-IoT (NB-IoT) service is being actively investigated with the apparition of Non-Terrestrial Network (NTN) and DtS-IoT concepts. Although some initiatives propose seamless and ubiquitous service, these features may not be required for IoT applications. This relaxes the requirements in the satellite constellation architecture, enabling it to be more sparse. The connection between sensors, satellites and ground segment becomes intermittent and discontinuous in these non-dense architectures. Delay/Disruptive-tolerant protocols are essential to coexist with this network characteristics. Unfortunately, traditional IoT protocols have not been designed with this delay-tolerant feature. This work tackles this challenge by integrating Delay-Tolerant Network protocols with NB-IoT architecture. Specifically, the integration is based on interconnecting the Bundle Protocol and IP traffic through a novel interface. This development has been divided in three phases: (1) The definition of an architecture and protocol stack to tackle NTN IoT scenarios with discontinuities, (2) the analysis from simulated data of the resulting protocol stack in a realistic scenario based on flooding prevention, and (3) the implementation and validation of it in a laboratory testbed. The proposed case study uses a Direct-to-Satellite IoT architecture to create an early warning flooding detection system. The simulation results provide insights of the achieved performance with these architectures when servicing hundreds of sensing nodes.

Impact of Renewable Energy Resources on the Performance of DTN Networks in the Context of Hierarchical Routing Tree Topology (HRTT)

Delay-Tolerant Networks (DTN) are mobile networks specifically designed to operate in challenging wireless environments where connectivity is not guaranteed, and various issues such as frequent disconnections, long delivery delays, low delivery rates, and high error rates are common. One of the major problems of DTN networks is limited energy resources which impose strict constraints on the operational lifespan of DTN nodes. To solve these problems, we propose the adoption of a long-term strategy for energy management, based on the exploitation of renewable energies and the improvement of the HRTT topological architecture through the direct integration of renewable energy sources within DTN nodes. Indeed, DTN nodes powered by renewable energy resources, such as solar energy, have the potential to recharge themselves, extending their operational lifespan, increasing their storage and transmission capabilities, and reducing dependence on non-renewable energy resources. In this article, we assess the impact of limited energy resources and renewable energy resources like solar panels on the energy performance of DTN networks in the context of the Hierarchical Routing Tree Topology (HRTT), taking into account the average remaining energy as a performance metric. The evaluation of energy performance and the implementation of the HRTT topology are carried out using the ONE (Opportunistic Network Environment) simulator. According to the simulation results, the average remaining energy of nodes using renewable resources is significantly higher compared to the initial energy levels of nodes for all DTN protocols adopted by the nodes in the context of the HRTT topology. However, the average remaining energy of nodes using limited resources is lower compared to their initial energy levels for all DTN protocols adopted by the nodes in the context of the HRTT topology.

Development of Delay-Tolerant Networking Protocols for Reliable Data Transmission in Space Networks: A Simulation-Based Approach

Development of Delay-Tolerant Networking Protocols for Reliable Data Transmission in Space Networks: A Simulation-Based Approach

Evaluation of delay tolerant network routing protocols for data streaming through LEO constellation

In the Era of Mega Low Earth Orbit (LEO) satellite constellation, the efficient networking through Inter-Satellite Links (ISLs) plays a vital role in its mission success. The deployed networking resources must be justified regarding the feasibility, reliability, and Quality of Service (QoS). The main challenge of such networks is the ISLs intermittence due to the dynamic nature of the constellation topology. In addition to the space environment. From this perspective, Delay Tolerant Network (DTN) protocols were proposed for alleviating the events of intermittence. This paper introduces a technique for using the discrete-event network simulator (NS3) for the simulation of LEO constellation networks. This technique considers the dynamic nature of network’s nodes in data streaming through ISLs. The paper presents a performance assessment of LEO constellation networks dedicated for forwarding the payload data through ISLs. The performance measures include both the delay and delivery ratio. The assessment considers different local resources such as transmitted power, Queue size, and transmission rate. The performance measures were applied for some selected DTN protocols such as “Epidemic” and “Spray and Wait”. The results illustrate the effects of different network resources and configurations that may affect the constellation mission.

Improving Bundle Routing in a Space DTN by Approximating the Transmission Time of the Reliable LTP

Because the operation of space networks is carefully planned, it is possible to predict future contact opportunities from link budget analysis using the anticipated positions of the nodes over time. In the standard approach to space delay-tolerant networking (DTN), such knowledge is used by contact graph routing (CGR) to decide the paths for data bundles. However, the computation assumes nearly ideal channel conditions, disregarding the impact of the convergence layer retransmissions (e.g., as implemented by the Licklider transmission protocol (LTP)). In this paper, the effect of the bundle forwarding time estimation (i.e., the link service time) to routing optimality is analyzed, and an accurate expression for lossy channels is discussed. The analysis is performed first from a general and protocol-agnostic perspective, assuming knowledge of the statistical properties and general features of the contact opportunities. Then, a practical case is studied using the standard space DTN protocol, evaluating the performance improvement of CGR under the proposed forwarding time estimation. The results of this study provide insight into the optimal routing problem for a space DTN and a suggested improvement to the current routing standard.

A Delay-Tolerant Network for Antarctica

Antarctica is the land of science. Every year, many studies are carried out in diverse disciplines. Some of these studies collect relevant data for their research with sensors. However, Antarctica's lack of telecommunication technologies hardens the possibility of automatizing this data collection. In most cases, the collection is done manually, limiting research projects' time and space scopes. Over the last years, some alternatives have been studied to deploy remote wireless sensor networks in Antarctica. Near-Vertical Incidence Skywave (NVIS) communications are an example of these alternatives. However, NVIS presents problems that cannot guarantee persistent end-to-end connectivity. For this reason, this article assesses adapting a delay-tolerant network protocol, the Bundle Protocol, to deliver sensor data reliably through an NVIS network. The scenario is developed and tested in the Riverbed Modeler simulator, and performance is evaluated through a trustworthiness model. A practical testbed is also presented.

Adaptive secured position based routing protocol for efficient data transmission in Vehicular Adhoc network

Variable number of cars equipped with radio devices allow the driver to exchange messages seamlessly across the network, no matter where they are in relation to each other. Inter-vehicle video transmission is an important feature of the VANET. Foreseeing the development of commercial service, video streaming appears to be a practical answer to a number of expected services. For data transmission in vehicular ad hoc networks, this study examines non-delay-tolerant and delay-tolerant network protocols, respectively.Different performance metric criteria like Packet Loss ratio, Number of Packet delivered, Route Length are evaluated.

Ring Road Networks: Access for Anyone

Several billion people currently lack reliable access to the Internet and thus to a tremendous source of knowledge. In this article, we describe a field-tested communication approach combining CubeSat platforms and delay-tolerant networking (DTN) solutions to provide asynchronous connectivity to populations and regions that are underserved by the Internet. The resulting class of networks is known as ring road networks (RRNs), a networking approach that is built on technology developed for the construction of a solar system Internet. The necessary self-sufficiency of DTN nodes enables network access to be deployed incrementally at low cost, supporting communities that cannot be profitably served by Internet satellite constellations. We present the RRN architecture and evaluate the expected performance by means of simulations. Based on the latter, we discuss µD3TN: a lightweight and open source DTN protocol stack for RRNs and other DTN classes. µD3TN has been flight-tested in ESA's OPS-SAT in low Earth orbit during December 2020 and May 2021. This work discusses the experiment results as we validated the RRN approach in concrete application use cases. The reported outcomes motivate a new application domain.

Escape Path Obstacle-Based Mobility Model (EPOM) for Campus Delay-Tolerant Network

In Delay-Tolerant Networks (DTNs), humans are the main carriers of mobile devices, signifying that human mobility can be exploited by extracting nodes’ interests, social behavior, and spatiotemporal features for the performance evaluation of DTNs protocols. This paper presents a new mobility model that describes students’ daily activities in a campus environment. Unlike the conventional random walk models, which use a free space environment, our model includes a collision-avoidance technique that generates an escape path upon encountering obstacles of different shapes and sizes that obstruct pedestrian movement. We evaluate the model’s usefulness by comparing the distributions of its synthetic traces with realistic traces in terms of spatial, temporal, and connectivity features of human mobility. Similarly, we analyze the concept of dynamic movement clusters observed on the location-based trajectories of the studied real traces. The model synthetically generates traces with the distribution of the intercluster travel distance, intracluster travel distance, direction of movement, contact duration, intercontact time, and pause time similar to the distribution of real traces.

Routing in Delay-Tolerant Networks under uncertain contact plans

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 exported to local-knowledge (L-RUCoP) and Contact Graph Routing extensions (CGR-UCoP) which can be implemented in the existing DTN protocol stack. RUCoP and its derivations are evaluated in a first extensive simulation benchmark for DTNs under uncertain contact plans comprising both random and realistic scenarios. Results confirm that RUCoP and L-RUCoP closely approach the ideal delivery ratio of an oracle, while CGR-UCoP improves state-of-the-art DTN routing schemes delivery ratio up to 25%.

Autonomous Delay Tolerant Network Management Using Reinforcement Learning

Delay tolerant networks (DTNs) offer a set of standardized protocols to enable Internet-like connectivity across the solar system. Unlike other protocols such as the Transmission Control Protocol (TCP) and the Internet Protocol (IP), DTN protocols are robust to end-to-end connection disruptions and long delays. Although the behavior of DTN core protocols is well understood, management of DTNs is still an area of active research. This paper uses reinforcement learning (RL) to automate the management of a DTN node consisting of an orbital relay between the moon and Earth. More specifically, the RL agent is in charge of deciding when to drop packets, when to change the data rate of the neighbor node links, when to reroute bundles to crosslinks, or when not to change any network parameter. The agent’s goal is to maximize the bits received by the Deep Space Network while minimizing the capacity allocated to all controlled links, and control the buffer utilization to avoid memory overflows. To assess the potential of using RL in DTN management, the performance of the trained RL agent is benchmarked against other non-RL-based policies in a realistic lunar scenario. Results show that the RL agent provides the highest reward, outperforming all non-RL policies in this scenario.

An Efficient Routing Protocol with Overload Control for Group Mobility in Delay-Tolerant Networking

In delay-tolerant networking (DTN), messages are delivered to destination nodes by using opportunistic contacts between contact nodes, even if stable routing paths from source nodes to destination nodes do not exist. In some DTN network environments, such as military networks, nodes movement follows a group movement model, and an efficient DTN routing protocol is required to use the characteristics of group mobility. In this paper, we consider a network environment, where both intra- and intergroup routing are carried out by using DTN protocols. Then, we propose an efficient routing protocol with overload control for group mobility, where delivery predictability for group mobility is defined and proactive overload control is applied. Performance evaluation results show that the proposed protocol had better delivery ratios and overhead ratios than compared protocols, although the delivery latency was increased.

Network evaluation and protocol deployment for complex deep-space networks based on DTN

Previous research on deep-space networks based on delay-tolerant networking (DTN) has mainly focused on the performance of DTN protocols in simple networks; hence, research on complex networks is lacking. In this paper, we focus on network evaluation and protocol deployment for complex DTN-based deep-space networks and apply the results to a novel complex deep-space network based on the Universal Interplanetary Communication Network (UNICON-CDSN) proposed by the National Space Science Center (NSSC) for simulation and verification. A network evaluation method based on network capacity and memory analysis is proposed. Based on a performance comparison between the Licklider Transmission Protocol (LTP) and the Transmission Control Protocol (TCP) with the Bundle Protocol (BP) in various communication scenarios, a transport protocol configuration proposal is developed and used to construct an LTP deployment scheme for UNICON-CDSN. For the LTP deployment scheme, a theoretical model of file delivery time over complex deep-space networks is built. A network evaluation with the method proposed in this paper proves that UNICON-CDSN satisfies the requirements for the 2020 Mars exploration mission Curiosity. Moreover, simulation results from a universal space communication network testbed (USCNT) designed by us show that the LTP deployment scheme is suitable for UNICON-CDSN.

A new approach buffer-efficient disruption tolerant protocol in vehicular delay-tolerant network

As the percentage of Vehicles are increasing on roads, Vehicular Ad-hoc network have reached to a significant interest of the researcher in recent times. V2V network and V2I are prominent as an organized solution for attaining safety for moving vehicles on road and transmitting data for a secure journey while driving and transferring data in the form of message from one vehicle to other. VDTN is a kind of Delay Tolerant Networks (DTNs), to provide reliable and efficient communications. Various routing protocols have been used previously in VDTN to enhance the performance of the network in terms of forwarding information in the form of messages to their preferred locations. In this paper, we introduce a novel protocol called Buffer-Efficient Disruption Tolerant Routing Protocol (BEDTRP) to improve delivery delay, overhead and latency. This protocol significantly improves the communication performance such as delivery ratio and overhead in terms of increasing buffer size and bandwidth. Evaluation results show that the proposed method BEDTRP achieves high bandwidth utilization performance to provide better delivery ratio, lower delivery delay, and low overhead against buffer changes. We used ns-2 network simulator to implement Delay tolerant network protocol.

Performance of Delay Tolerant Network Protocol in Smart City Scenario

The smart city is being developed in many big cities to support local governments for resources and infrastructure optimization in terms of enhancing services for the citizen. Large investment costs are required to implement a communication network for the smart city infrastructure (i.e. Internet of Things (IoT) devices) using 4G or Wi-Fi networks. This study aims to implement Delay Tolerant Network (DTN) as a low-cost alternative network for the smart city. We use Surabaya smart city plan scenario in which smart mobility services are provided in city transportation and infrastructure. The IoT devices are installed in numerous locations and continuously transmit messages to the monitoring server located in the city hall, bus and car employed as a DTN node. In this paper, as a preliminary research, we investigate the performance of well-known DTN routing protocols (Epidemic, Maxprop, and ProphetV2) with our proposed protocol called Spray and Hop Distance (SNHD). The evaluation is performed using the ONE simulator in terms of the number of delivered messages, the average latency, and the overhead ratio. The results show the performance of SNHD is better than the well-known DTN protocols in various conditions when the total size of delivered messages is large. Unfortunately, none of those routing protocols has a good performance in all of the scenario conditions. In the future, we desire to implement this system in real smart city system in Surabaya and do simulation with more realistic scenario such as real traffic-trace.

DTN Routing Hierarchical Topology for the Internet of Things

Abstract New technologies have been expanding rapidly in recent years. These new technologies require new communication systems, such as delay tolerant networks (DTN). However, establishing communications is not enough. Networks must allow data to be exchanged and these data must be understood by the entities that receive them. Although a lot of DTN routing protocol has been proposed for DTN networks, but with the emergence of new technological applications such as drones, the Internet of Things, etc., the DTN routing protocol is still in use. It is desirable to develop a feasible, reliable and robust protocol for this new range of applications. In this work, we will present a DTN protocol for the Internet of Things (IoT) applications.

Networking in Interstellar Dimensions: Communicating With TRAPPIST-1

The recent discovery of potentially habitable planets orbiting the TRAPPIST-1 system intensified interest in interstellar exploration. In these challenging mission concepts, communication protocols would need to cope with unprecedented signal propagation delays. In this paper, we propose and explore delay tolerant networking (DTN) technologies and analyze in a case study based on the TRAPPIST-1. Results suggests that DTN protocols features could become a valuable means to achieve data delivery in future interstellar networks.

Delay Tolerant Network assisted flying Ad-Hoc network scenario: modeling and analytical perspective

Flying Ad-Hoc networks (FANET) are the extended paradigm of the mobile Ad-Hoc networks and, perhaps, one of the most emerging research domains in the current era. A huge number of tangible applications have been developed in this domain. The main advantages of such networks are their easy deployment, scalability, and robustness. However, the sparseness of these networks is an inherent characteristic that is known to be a bottleneck. The main objective of this work was to provide an alternative solution for the intermittently connected FANET by considering the philosophy of the Delay Tolerant Network (DTN) approach. To realize the functionality of the DTN protocols in a three-dimensional (3D) space, a social FANET model is proposed. FANET nodes are supposed to have a sparse node density. Fundamentally, the proposed DTN assisted Flying Ad hoc Network exploits the DTN routing and mobility features. The new mobility modeling for 3D spaces was re-engineered and tested with well-known routing protocols to analyze the performance of the model based on node speed, density, buffer, latency, message overhead, and power consumption. The effectiveness of 3D mobility models has also been compared against the one of classical models. The obtained results reflect a significant enhanced performance of the suggested DTN protocol for sparse FANET in a social scenario.

A Congestion Control Approach for Licklider Transmission Protocol

Delay Tolerant Networks (DTN) are designed to deal with the long delay of space network and frequent link interruption, in 2002. Licklider Transmission Protocol (LTP) was designed to replace the Internetworking Protocol (IP) and Transmission Control Protocol (TCP) in the DTN protocol stack. However, LTP has no congestion control mechanism. If a packet is dropped, the performance of the network will be worse. To deal with this problem, this paper proposes the Ecn-based TFRC Licker Transmission Protocol (ET-LTP) which extends the LTP data packet to record the network condition. The ET-LTP refers to congestion control approach applied on streaming media transmission on this question. A detailed control strategy is proposed in this paper as well. Finally, the simulations are built to test the performance of the ET-LTP. The results prove that the ET-LTP is more robust than LTP when facing the congestion.

Study of E-mail Data Services based on Delay Tolerant Network in The Riau Province Border Region

Indonesia is an archipelagic country that is geographically unique, where most of the land has uneven land contours because it consists of mountains and valleys. This condition is one of the causes of the inequality of information dissemination even though the ICT infrastructure has supported and internet services are also available. Topographical factors and inequality of information dissemination pose digital deviations in the community, especially border areas in Riau Province which have not been able to enjoy internet services in some of the regions. Even though the process of data transmission to other regions is needed by both government agencies placed in border areas and the general public who need internet services for data transmission (text, audio, and video). Delay Tolerant Network (DTN) technology is a network protocol that allows communication networks to be applied in extreme environments that have long delay characteristics, high loss rates, and low connectivity levels. With DTN, internet services can be implemented and presented cheaply using only DTN Router which will move to areas that are not reachable by the internet and collect email data digitally. Furthermore, DTN Router and processes every transmission request from/to the border regions with extreme topography. By using the Flooding method applied to the DTN protocol, testing of e-mail data packet transmission from simulations at several locations in Riau is considered to have high data loss. Testing modeled by several computers with DTN, doing a bundle of data packages, transmitting to destinations and assessing the efficiency of their success. The test results show that the data transmission process in extreme areas using DTN protocol, Indicates that the larger the size of the file sent. So, the greater the time needed for data transmission. Approximate of time is needed of transmission data of the 95MB file that is 4,1 second..