A cooperative mobile throwbox-based routing protocol for social-aware delay tolerant networks

Majority of the existing Delay Tolerant Network (DTN) routing protocols, attempt to minimize one of the popular DTN routing indices, i.e. message delay, forwarding count and storage. However, for many DTN applications such as distributing commercial content, targeting the best performance for one index and compromising the others is insufficient. A more practical solution would be to strike a balance between multiple of these indices. Gain Dissemination Protocol (GDP) is one of the protocols which targets this aim by introducing a gain concept which tries reach a maximum gain of delivery by keeping the balance between the value achieved via delivering the packet to the destination and the forwarding cost involved with that. In this paper, we focus on characterizing the GDP protocol in the scope of mobility. We also propose an upper bound for gain in multicast routing problem, i.e. the Union of Unicast Benchmark (UUB) and compare the performance of a few DTN routing protocols with the former. This eventually reveals the performance scope of a potential gain-aware DTN dissemination protocol.

In recent years, several investigations have been made on "challenged network" [also known as, delay tolerant network (DTN)] architectures highlighting their advantages and disadvantages. In spite of its inherent shortcomings of unreliability and delay, smart-phone based opportunistic network is gaining immense popularity in the research community due to its applicability in different adverse and extreme communication scenarios where traditional communication infrastructure is either unavailable or incapacitated for a long time. Considerable research has been conducted till date to design efficient network architecture for emergency data dissemination in intermittently connected/challenged networks. Different architectures (ranging from flat to multi-tier) are proposed for implementing opportunistic DTN keeping in view of specific application requirements. However, very few of these proposed architectures have been examined from the perspective of a post disaster communication. Moreover, most DTN architectures are designed by aiming towards increasing delivery probability and reducing latency and as a whole, maximizing network throughput; with very little emphasis on its energy efficiency. The impact of different mobility patterns on existing DTN routing algorithms with respect to data dissemination and energy consumption has also not been studied so far. Our objective, in this paper, is to investigate the impact of different mobility patterns on existing DTN routing protocols and existing DTN architectures and subsequently, come up with a suitable energy efficient DTN framework combining suitable architecture and routing protocol that may be used to offer different disaster management services during post-disaster relief operation. We have done an extensive simulation on ONE simulator with different categories of well-known existing DTN architectures, mobility models, DTN routing protocols to study the network performance in terms of delivery probability, energy efficiency and overhead ratio. Based on the simulation results, we have tried to figure out a suitable combination of energy efficient architecture, mobility model and routing protocol that fits well in the post disaster communication scenario.

A Delay Tolerant Network (DTN) is a network capable of handling long delays and data loss efficiently in various challenged scenarios and environments. Owing to the mentioned challenges, it becomes crucial to study how the routing protocols are designed to adapt in such networks. Currently, the research in this domain is focused on the improving the data delivery ratio and minimizing delays in the routing protocols. This paper reviews state-of-the-art routing protocols for Delay Tolerant Networks (DTNs) as well as performs their comparative analysis. DTN routing protocols are grouped into four categories viz encounter based, time based, infrastructure based and hybrid & others. This categorization depends on the information they use for relay selection routing. We have also discussed some of the inherent drawbacks such as energy consumption, delivery rates and buffer constraints of the existing routing algorithms. We have also conducted an empirical analysis and observed the performance of the most popular existing algorithms of encounter and time based category. This paper offers a widespread study of the routing protocols with their pros and cons.

Delay-Tolerant Networks are characterized by not having permanent end-to-end connections, often leading to intermittent connectivity, long and variable delays and high error rates. Mobile Social Networks are particular scenarios on which nodes are seen as individuals with inherent social habits, having wireless communication devices. In this paper a routing protocol based on the social property of Friendship is proposed. The protocol allows nodes to consider other nodes to be friends if they maintain contact frequently, regularly and in long-lasting sessions. The forwarding scheme consists in only delivering the message to nodes which are friends of the destination. To evaluate the performance of this protocol, the ONE Simulator was used. The Friendship Protocol performance was analyzed and compared to three other routing protocols while varying the network load. The simulation results showed that the Friendship Protocol could reach a high delivery rate and a very low overhead. A dynamic threshold version of the protocol was also proposed, on which the friendship threshold changes over time as it corresponds to a portion of the best friends. The results of this dynamic version were similar to the fixed threshold version, but with roughly half the overhead.

A social-aware routing protocol for opportunistic networks

In a Delay Tolerant Network (DTN), the nodes have intermittent connectivity and complete path(s) between the source and destination may not exist. The communication takes place opportunistically when any two nodes enter the effective range. One of the major challenges in DTNs is message forwarding when a sender must select a best neighbor that has the highest probability of forwarding the message to the actual destination. However, finding an appropriate route remains an NP-hard problem. This paper presents a concept of Checkpoint (CP) based message forwarding in DTNs. The CPs are autonomous high-end wireless devices with large buffer storage and are responsible for temporarily storing the messages to be forwarded. The CPs are deployed at various places within the city parameter that are covered by bus routes and where human meeting frequencies are higher. For the simulative analysis a synthetic human mobility model in ONE simulator is constructed for the city of Fargo, ND, USA. The model is tested over various DTN routing protocols and the results indicate that using CP overlay over the existing DTN architecture significantly decreases message delivery time as well as buffer usage.

The Delay Tolerant Networks (DTNs), are emerging as one of the most efficient network that allow nodes in intermittently connected networks to communicate with each other. They are designed to overcome high latency and lack in connectivity due to poor infrastructure and short range radios. However, the DTNs relay nodes have limited resources (i.e., low-power RF module, low computation capacity, limited buffer size, short battery power). Moreover, the DTNs routing protocols, which route the message between a source and a target destination, are very numerous, including the famous Epidemic routing, k-hop routing, prophet routing. Consequently, We found that it would be valuable to compare these prominent opportunistic networks protocols under constraint of energy consumption in forwarding activity. We have done this using the ONE simulator and evaluated the schemes with regard to message delivery probability, energy efficiency.

A survey of routing and data dissemination in Delay Tolerant Networks

Generic prediction assisted single-copy routing in underwater delay tolerant sensor networks

Delay Tolerant Network(DTN) is a wireless network where source cannot have a handshake with the destination and source has to use a routing known as opportunistic routing to deliver the message to the destination. One of the most widely used routing protocol in DTN is Spray and Wait(SnW) routing protocol and there are a lot of methods to complete the spray phase, most popular is Binary SnW. In this paper, we are proposing a modified version of Binary SnW protocol referred as Hexago SnW. In this approach, we used hexagonal series instead of binary series. The comparison of Hexago SnW with other existing approaches shows that Hexago SnW gives better performance than others in term of overhead ratio, delivery ratio etc. In simulation, two groups of moving objects are used to show the working and performance evaluation of our proposed routing technique.

Usage of wireless gadgets is increasing day by day in both metropolitan and countryside localities. The network infrastructure does not reach all the localities; especially in rural areas, where the internet availability is inadequate to meet the network requirements. Devices in such rural locations will be out of the network for some period. This non-persistent connectivity problem can be solved by using the moving nodes as a carrier for data transmission. In this work, we classify the vehicular network into sparse, semi-sparse and dense network based on the number of static and moving nodes present in a location. In sparse and semi-sparse network, there won't be any continuous path between the source and destination nodes. In such networks, we can use Delay Tolerant Network (DTN) protocols for data transmission. In our work, we try to find the suitable DTN protocol for the sparse and semi-sparse network topology. The protocols considered in this work are Epidemic, Spray and Wait, and Maxprop and the parameters we analyzed are delivery ratio, average latency and overhead ratio. We simulated these protocols in a vehicular network with heterogeneous characteristics, for the dense, semi-sparse and sparse network topology. The routing protocols performance is analyzed by delivery ratio, average latency and overhead ratio using Opportunistic Network Environment (ONE) simulator for varying the message lifetime and node density.

SummaryIn Delay Tolerant Networks (DTNs), mobile nodes exploit encounter chances to transmit data via the established opportunistic link between encounter nodes. The transmission capacity between two encounter nodes is constrained by the duration of opportunistic links. How to transmit data efficiently is one of the fundamental and most important issues in DTNs. Recently, Random Linear Network Coding (RLNC) is proposed as a promising approach to improve data transmission efficiency in DTNs. To facilitate the development of deployment of RLNC based routing protocols, it is imperative to quantify the performance gain brought by RLNC in a rigorous and systematic way. In this paper, we develop an analytical model to evaluate the data transmission performance of RLNC based epidemic routing in DTNs. In the model, we consider that multiple unicast communication sessions compete for limited \capacity. Numerical results validate the effectiveness of our analytical model and demonstrate the significant performance improvement for data transmission in DTNs brought by RLNC. Our work of this paper provides a general tool for performance evaluation and useful guidelines for designing RLNC based routing protocols in DTNs. Copyright © 2015 John Wiley & Sons, Ltd.

A class of Delay Tolerant Networks (DTN), which may violate one or more of the assumptions regarding the overall performance characteristics of the underlying links in order to achieve smooth operation, is rapidly growing in importance but may not be well served by the current end-to-end TCP/IP model. Delay Tolerant Networks: Protocols and Applications takes you on a systematic exploration of DTN concepts, architectures, protocols, enabling technologies, and applications. Containing a wealth of illustrative material for ease of understanding, this one-stop reference discusses the various challenges associated with DTN. Written for a broad audience of researchers and practitioners, it supplies useful reference material for graduate students and senior undergraduate students in courses of networking, wireless, and mobile communications. Starting with an accessible introduction to DTNs, their architecture, bundle protocols, and routing schemes, the book provides authoritative coverage of: DTN Routing Energy-Aware Routing Protocol for DTNs A Routing-Compatible Credit-Based Incentive Scheme R-P2P: a Data-Centric Middleware for Delay Tolerant Applications Mobile Peer-to-Peer Systems over DTNs Delay-Tolerant Monitoring of Mobility-Assisted WSN Message Dissemination in Vehicular Networks DTN Protocols for Space Communications DTN for Satellite Communications Reporting on the latest developments in these domains, the distinguished panel of contributors supplies a realistic look into the future of networking. Complete with sections that summarize open issues in each domain, this book arms you with the understanding and methods required to make an impact on the advancement of these emerging networks that continue to grow in importance.

In challenged networks, such as opportunistic networks or Delay Tolerant Networks (DTNs), due to frequent network partition an end-to-end connection between source and destination may not always be possible due to nodes move unpredictably with high speeds. For such type of networks, traditional routing protocols fails to transmit and also no guarantee on delivery of data to specified destination because these protocols deliver data definitely whenever there exists continuous end-to-end connectivity between source and destination over time. To provide efficient routing for such networks replication based routing schemes were proposed to achieve higher delivery probability. Unlike Internet protocols, Delay Tolerant Networks routing protocols follow store-carryforward mechanism to reduce packets dropping probability, tolerate delays and improve delivery performance in terms of delivery ratio and delivery latency. This paper defines the most efficient replication based routing protocols such as epidemic, PROPHET, spray and wait and Encounter based routing. This paper also explains how message TTL, buffer sizes and area of grid impact performance of replication based routing protocol in terms of delivery ratio and Average latency and overhead ratio.

While portable and wireless devices are pouring, a new network technology is needed as a breakthrough. The new network technology features large delays, intermittent connectivity, and absence of an end-to-end path from sources to destinations. A network which has one of those characteristics is called DTNs(Delay Tolerant Networks). The main 4 routing methods have been researched so far in extreme environment. In this paper, we look into the reliability of DTMNs(Delay Tolerant Mobile Networks) in several different situations, and propose an algorithm that selects a positive routine by sending the only information of its position when making a connection to a detected node. We simulate the proposed algorithm here in DTN using ONE simulator. As a result, it shows that the algorithm reduces the number of message transmission each node.