Communication In Delay Tolerant Networks Research Articles

A review on machine learning based routing protocols for delay tolerant networks

Nowadays, Delay Tolerant Network plays an important role in improving the communication between the network nodes. Applications of Delay Tolerant Network are disaster recovery, vehicular communication, sensor networks, interplanetary networks, and communication in remote and rural areas. Routing is one of the important tasks for enhancing the energy effectiveness of data transmission among the mobile nodes under network congestion and dynamic topology. Machine Learning-based routing algorithms are used for improving network communication in Delay Tolerant Networks. Its objective is to reduce the delay, minimize the overhead, reduce energy consumption, improve throughput, minimize packet loss, and efficient data transmission. This paper presents a comprehensive review of routing algorithms using machine learning for Delay Tolerant Networks.

CFDP PDU Tunneling Service over DTN Between Heterogeneous Deep Space Communication Assets

In space exploration missions, the spacecraft have limited computing resources. In particular, the communications environments for these spacecraft, whether in deep space or the cislunar region, are characterized by intermittent connectivity loss, long signal-propagation delay, and high bit-error rates between spacecraft and their ground stations. Delay-Tolerant Network (DTN) has been introduced to enable automated, efficient communication among flight-mission entities in these environments. However, most flight-mission entities are not yet equipped for DTN; a mechanism is needed whereby DTN-enabled entities and non-DTN-enabled entities can easily interoperate. The CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol (CFDP) is supported in both DTN and non-DTN communication fabrics, so perhaps CFDP file transmission can serve as the common communication medium that bridges the two. When CFDP runs without a Bundle Protocol (BP), it requires a more complex CFDP implementation, and multi-hop communication is more difficult to configure. This paper presents a tunneling mechanism that relays CFDP protocol data units (PDUs) between a non-DTN-enabled CFDP entity and a DTN-enabled CFDP entity. This enables CFDP-over-link implementations to bridge into BP networks to simplify multi-hop forwarding through the BP network. A proof-of-concept implementation of the tunneling service has been developed and tested using the Interplanetary Overlay Network (ION) DTN software to evaluate this concept of CFDP PDU relay/forward functionality to enable communication between the two heterogeneous space communication fabrics. Test setup, test results, and future work on the tunneling service are also discussed.

Pass and Run: A Privacy Preserving Delay Tolerant Network Communication Protocol for CyberVehicles

Editor’s note: In the era of intelligent transportation systems (ITS) due to vehicle-to-infrastructure (V2I) communication, data sent to roadside units (RSUs) can leak sensitive information of the vehicle such as driving patterns and history, and therefore may seriously violate privacy requirements. To address this very important research challenge, this article presents a Pass and Run protocol for the vehicular delay tolerant network (VDTN). The proposed protocol particularly addresses the vehicle location privacy problem. —Mohammad Al Faruque, University of California, Irvine

Defected Ground Based Fractal Antenna for S and C Band Applications

Defected ground based modified rectangular fractal patch antenna for mobile devices communication in Delay Tolerant Networks, Wireless sensor networks and Mobile Adhoc networks is being presented in this paper. In view of the overwhelming demand of small and light weight micro-chip patch antenna in wireless communication in the recent years the size of antenna has been reduced considerably. Wideband behaviour of antenna is achieved with improved values of performance parameters like gain, reflection coefficient (S11), Voltage Standing Wave Ratio (VSWR), radiation pattern and bandwidth. The proposed antenna covers various frequency bands like earth to space communication (2.17–2.2 GHz), satellite communication (2.3 GHz), wireless local area networks (2.4–2.484 GHz), Wi Fi (2.4 GHz for 802.11b and 802.11g), Radio Frequency Identification, Microwave oven, Bluetooth (2.45 GHz), Wireless Computer Networking (2.4 GHz), Mobile Wi-Max (2.5–2.69 GHz), Direct to home services (2.5–2.7 GHz), Wi-Max (3.3–3.6) Satellite Communication for Downlink (3.7–4.2 GHz) at various resonating frequencies. High Frequency Structural Simulator; v13 has been used to simulate the proposed antenna. The antenna has been designed and simulated using FR4 epoxy substrate with relative permittivity 4.4 and having size of 32 mm × 30 mm × 1.6 mm with line feeding technique. Ground plane has also made defective. The antenna shows the bandwidth of 2830 MHz with gain of 6.83 dB, reflection coefficient (S11) − 19.72 dB and VSWR of 1.23 at resonant frequency 2.85 GHz. Size of the antenna stands reduced by 38.73% with deflective ground surface and frequency shifted towards the lower side. The antenna operates from 2.05 to 4.88 GHz covering S and C band applications.

Hybrid Fractal Antenna Using Meander and Minkowski Curves for Wireless Applications

This paper describes a novel design of Minkowski and Meander curves based hybrid fractal antenna for mobile devices used for communication in delay tolerant networks, wireless sensor networks and mobile adhoc networks. Meander curve improves the impedance bandwidth. Minkowski fractal curve gives its contribution to make antenna multiband. The proposed antenna resonates at five frequencies 1.98, 5.94, 10.61, 12.73, 14.85 GHz. Prior to fabrication, better performance parameters such as return loss, radiation pattern, gain, current distribution, impedance, VSWR are achieved. The maximum bandwidth 2.83 GHz and gain 9.0 dB at 2.4 GHz are achieved. The proposed antenna can be used for various applications like Bluetooth, Wi-Fi, Wi-Max, Wi-Bro, AWS, GPS, S-DMB, WLAN 802.11b/g and DTH services etc. Simulated and measured results are compared and are found in agreement with each other.

A trust-based approach for securing data communication in delay tolerant networks

The proliferation of network technologies drives many different network architectures to provide huge variety of services and contents to end clients. This task becomes more difficult when we are in networks with intermittent connections, called delay tolerant networks (DTN) where security is an important issue. In this paper, we propose a trust-based approach to secure data transfer in DTN in the presence of malicious transporters. Our proposal is intended to a DTN architecture which includes several sub-networks geographically dispersed in isolated regions and having an intermittent access to an infrastructure-based network (like internet). Our approach is based on a particular web-of-trust, which is formed based on existing social relationship among clients and transporters. We conducted intensive simulations and the obtained results show that it offers high packet delivery rate and resists against malicious transporter's behaviour.

A trust-based approach for securing data communication in delay tolerant networks

A trust-based approach for securing data communication in delay tolerant networks

Autonomous drone for delay-tolerant networks in indoor applications

This article presents the idea and application of autonomous drones as mobile message ferries in delay-tolerant networks. The delay-tolerant network communication bases on messages ferrying called store-carry-forward paradigm. The messages ferrying can be realized by drones—an autonomous flying robots. For indoor application, drones are equipped with the sensors for distance and obstacle detection. The use of drones can be particularly effective in emergency scenarios where the human-rescuers’ activity is impossible due to hard unhealthy conditions. Our solution was tested in indoor scenario. The test results demonstrate good performance of our solution.

Practical Bloom filter based epidemic forwarding and congestion control in DTNs: A comparative analysis

Epidemic forwarding has been proposed as a forwarding technique to achieve opportunistic communication in delay tolerant networks (DTNs). Even if this technique is well known and widely referred, one has to address several practical problems before using it. Unfortunately, while the literature on DTNs is full of new techniques, very little has been done in comparing them. In particular, while Bloom filters have been proposed to exchange information about the buffer content prior to sending information in order to avoid redundant retransmissions, up to our knowledge no real evaluation has been provided to study the tradeoffs that exist for using Bloom filters in practice. A second practical issue in DTNs is buffer management (resulting from finite buffers) and congestion control (resulting from greedy sources). This has also been the topic of several papers that had already uncovered the difficulty to acquire accurate information mandatory to regulate the data transmission rates and buffer space. In this paper, we fill this gap. We have been implementing a simulation of different proposed congestion control schemes for epidemic forwarding in ns-3 environment. We use this simulation to compare different proposed schemes and to uncover issues that remain in each one of them. Based on this analysis, we proposed some strategies for Bloom filter management based on windowing and describe implementation tradeoffs. Afterwards, we propose a back-pressure rate control as a well as an aging based buffer managing solution to deal with congestion control. By simulating our proposed mechanisms in ns-3 both with random-waypoint mobility and realistic mobility traces coming from San-Francisco taxicabs, we show that the proposed mechanisms alleviate the challenges of using epidemic forwarding in DTNs.

Distribution of inter-contact time: An analysis-based on social relationships

Communication in delay tolerant networks (DTNs) relies on message transport by mobile nodes, and a correct understanding of the node mobility characteristics is therefore crucial to the design of an efficient DTN routing protocol. However, previous work has mainly focused on uncovering all behaviors of node movement, which is not conducive to accurately detecting the specific movement characteristics of a different node. In this paper, we seek to address this problem based on a consideration of social relationships. We first consider social ties from both static and dynamic perspectives. For a static perspective, in addition to certain accidental events, social relations are considered for a long time granularity and tend to be stable over time. For a dynamic perspective, social relations are analyzed in a relatively short time granularity and are likely to change over time. Based on these perspectives, we adopted different efficient approaches to dividing node pairs into two classes, i.e., familiar and unfamiliar pairs. A threshold approach is used for static social ties whereas a density-based aggregation method is used for dynamic social relationships. Extensive experimental results show that both familiar and unfamiliar node pairs have the same inter-contact time distribution, which closely follows a power-law decay up to a certain point, beyond which it begins to exponentially decay. The results also demonstrate that the inter-contact time distribution of familiar pairs decays faster than that of unfamiliar pairs, whether from a static or dynamic perspective. In addition, we also analyze the reason for the difference between the inter-contact time distributions of both unfamiliar and familiar pairs.

Supporting Navigation in Multi-Robot Systems through Delay Tolerant Network Communication

In this paper we study a problem of navigation in networked multi-robot systems. The robots are deployed in a confined area, where they move around and solve tasks. They communicate with each other through an infrared communication device, so that an ad hoc network is formed among them. Due to the limited range and line of sight nature of the infrared communication, this network has intermittent connectivity. The question we address is how a particular robot can use this network to find a target location that is indicated by another robot (e.g., the other robot has identified a task to be serviced by the searching robot). All other robots are involved in tasks of their own, and do not change their movements to help the searching robot find its destination. However, they do offer support by forwarding messages over the network. We propose a new algorithm based on routing in ad hoc and delay tolerant networks that can run on the network formed between the robots and provide navigation information to the searching robot. We evaluate the validity of our approach both in simulation and through an implementation on a group of 16 e-puck robots.