Prophet Routing Research Articles

Cooperation in Opportunistic Networks: An Overlay Approach for Destination-Dependent Utility-Based Schemes

In destination-dependent utility-based schemes, data forwarding is stimulated when a node presents next-hop fitness to destination higher than the current custodian of a message. However, these schemes do not enforce any mechanism to ensure cooperative participation, and altruistic behavior is taken as an assumption, instead. Therefore, a wide range of existing schemes known to provide effective performance may fail in pragmatic settings afflicted with selfish participants. In this paper, we propose a novel cooperation framework which is deployed as an overlay to assist data forwarding utility-based schemes. Effectiveness of our framework is evaluated through intensive simulations with PRoPHET and MARS routing.

An Improved PRoPHET Routing Protocol through the Restriction of Message Duplication

An Improved PRoPHET Routing Protocol through the Restriction of Message Duplication

Data dissemination using interest-tree in socially aware networking

Socially aware networking (SAN) exploits social characteristics of mobile users to streamline data dissemination protocols in opportunistic environments. Existing protocols in this area utilized various social features such as user interests, social similarity, and community structure to improve the performance of data dissemination. However, the interrelationship between user interests and its impact on the efficiency of data dissemination has not been explored sufficiently. In this paper, we analyze various kinds of relationships between user interests and model them using a layer-based structure in order to form social communities in SAN paradigm. We propose Int-Tree, an Interest-Tree based scheme which uses the relationship between user interests to improve the performance of data dissemination. The core of Int-Tree is the interest-tree, a tree-based community structure that combines two social features, i.e., density of a community and social tie, to support data dissemination. The simulation results show that Int-Tree achieves higher delivery ratio, lower overhead, in comparison to two benchmark protocols, PROPHET and Epidemic routing. In addition, Int-Tree can perform with 1.36 hop counts in average, and tolerable latency in terms of buffer size, time to live (TTL) and simulation duration. Finally, Int-Tree keeps stable performance with various parameters.

CMP: A Context Information-based Routing Scheme with Energy-based Message Prioritization for Delay Tolerant Networks

Communication infrastructure supports wide variety of mobile services such as photo and file sharing, location tracking, social network services and instant messaging. However, instances like power-loss and natural disasters disrupt these communication infrastructures unable to render support to these mobile services. Delay-tolerant networks (DTNs) offer a solution to these problems at hand. By utilizing mobility and opportunistic contacts among mobile devices, a plausible communication network can be establish and enable support to mobile applications. This paper presents an energy-efficient, reliable message delivery routing scheme with message prioritization rules for DTN. It uses the context information of nodes (mobile devices) such as the contact history (location and time of contact), speed/velocity, moving direction to determine the best forwarders among nodes in the network. The remaining energy of the nodes is also used to determine the message types a node can deliver successfully. The simulation results show that proposed approach outperforms Epidemic and Prophet routing schemes in terms of delivery ratio, overhead ratio, delivered messages per types and remaining energy.

Analysing social behaviour and message dissemination in human based delay tolerant network

Recent advances in mobile communication shows proliferation in networks formed by human carried devices known as the pocket switched network (PSN). Human beings are social animals. They tend to form groups and communities, and have repetitive mobility pattern which can be used to disseminate information in PSNs. In this paper, we give a deeper insight to the nature of community formation and how such information can be used to help opportunistic forwarding in mobile opportunistic networks. Using real world mobility traces, we first derive the adjacency list for each node and form the contact graph. Using tools from social network analysis we then determine various node properties like centrality and clustering coefficient and graph properties like average path length and modularity. Based on the derived graph properties, node encounter process and nature of message dissemination in PSNs, we propose two social based routing, known as the contact based routing and community aware two-hop routing. We compare the proposed routing techniques with generic epidemic and prophet routing and Bubble-Rap, a social based routing. Results show that the proposed algorithms is able to achieve better delivery ratio and lower delay than Bubble Rap, while reducing the high overhead ratio of epidemic and prophet routing.

Using known vectors to improve data dissemination in opportunistic networks

An opportunistic network is a type of challenged network in which contacts are intermittent, an end-to-end path rarely exists between the source and the destination, disconnection and reconnection are common occurrences, and link performance is highly variable or extreme. Conventional methods of data dissemination in opportunistic networks rely on a meta-message exchange scheme, called the summary vector (SV), to prevent redundant transmission of data bundles that already exist on receivers. We consider that the SV scheme is costly in terms of the data transmission overhead, which is unaffordable in opportunistic networks. Hence, we propose an alternative scheme, called the known vector (KV), to improve the efficiency of meta-message exchanges for data transmission in opportunistic networks. Using a comprehensive set of simulations with realistic network scenarios, we demonstrate that the KV scheme can be easily integrated into existing opportunistic network routing protocols (e.g., Epidemic and PRoPHET routing). Moreover, it can reduce the communication overhead significantly, thereby improving energy efficiency for data transmission in opportunistic networks.

DF++ : an adaptive buffer-aware probabilistic delegation forwarding protocol for Delay Tolerant Network

The delegated forwarding (DF) curb transmissions by forwarding the message to a node that holds high quality value seen by the message. However, DF assumes infinite buffer space that is not possible in real time applications. In addition, quality value computation considers the encountering history and does not account for additional network parameters such as aging and transitive connectivity. In this paper, we have proposed a routing protocol called as DF++ that compute quality value based on probabilistic model used in PRoPHET protocol and forwards the message to current node by adaptive computation of available buffer space. We have compared performance of DF++ with DF, Epidemic and PRoPHET routing protocols. The proposed DF++ has higher delivery probability and fewer message drop and transmissions.

Extension of Delay Tolerant Network’s Routing Protocols for Preventing Excessive Utilization of Resources

The routing algorithms of DTN have the inbuilt storage management scheme such as Hop based TTL (Spray and Wait) or passive cure (Potential-based Entropy Adaptive Routing PEAR). There has been a significant amount of work in the past regarding buffer management policies. In this paper, we have proposed a new message deletion policy for multi-copy routing schemes. In this scheme, message delivery information is communicated to the other nodes in the network for removing useless bundles from the network, which prevents the nodes from the buffer overflow problem and avoid transfer of useless message replicas thus relaxing the resources of the nodes. We evaluate our proposed method by simulating network, on four major DTNs routing algorithms: Epidemic, Spray and Wait, ProPHET and MaxProp. The simulation results clearly show significant improvement in the value of delivery probability and the overhead ratio for an Epidemic, Spray and Wait, and Prophet routing protocols.

Analysis and evaluation of probabilistic routing protocol for intermittently connected network

Intermittently connected network often referred to as Delay/Disruption Tolerant Network which is an infrastructure less network suffers from intermittent connection i.e. a connected path from the source to the destination may be absent or a given destination may not be reachable at the moment a message is sent. As a result traditional routing protocols for Ad hoc networks cannot serve the purpose of this type of intermittently connected network. PROPHET routing protocol works on the principle of history of encounters and transitivity. It is called Probabilistic routing protocol since it uses a parameter 'Delivery of Predictability'. In this paper the architecture of delay tolerant network is being discussed and PROPHET protocol is implemented.

Adaptive message size routing strategy for delay tolerant network

Delay tolerant network (DTN) is a kind of computer network that suffer from the frequent disconnections, network partitioned and unstable network connectivity, therefore maintaining an uninterrupted route from source to destination is not possible. Therefore, the transmission of message is achieved via intermediate nodes by adopting a novel transmission mechanism called store-carry and forward where node stores the incoming message in its buffer, carries it while moving and forward it when it comes in the transmission range of other nodes. DTN routing protocols can be either single copy or multi copy. In single copy protocols, the node forwards the unique copy of message along a single path. These protocols suffer the long delivery delay. In multi copy protocols, the node diffuses multiple copies of same message along dissimilar paths. Thus, message can reach destination via more than one path. However, the replication process consumes high volume of network resources such as buffer space, bandwidth and node energy. The probabilistic routing strategies for instance PRoPHET Protocol minimizes the consumption of resources and forwards a message to a custodian by using a metric of delivery probability. The probability describes the suitability of a node to meet the destination of message. However, when node mobility pattern is not symmetric the probabilistic computations cannot predict the accurate forwarding decision. In this paper, we have proposed a novel message forwarding strategy called Adaptive Message-Size Routing strategy (AMRS) by which a node handovers the copy of message to its neighboring nodes by using a metric named as mean threshold (MTH). We have compared the performance of AMRS with Epidemic and PRoPHET routing protocols. The proposed routing strategy has performed better in terms of maximizing delivery probability while minimizes message drops and number of transmissions.

Application of Computational Intelligence Paradigm in the Probabilistic Routing for intermittently connected network

In this project an approach is being made to use Fuzzy Logic(a computational intelligence paradigm) in the Probabilistic routing protocol for Intermittently connected network: Delay Tolerant Network. Communication between two mobile nodes in an infrastructure less network is possible if they are within the wireless communication range. Delay Tolerant Network (or DTN) is not only an infrastructure less network but it also suffers from intermittent connection i.e. there is not always a connected path from the source to the destination. As a result traditional routing protocols cannot serve the purpose of this type of network. A passive routing protocol for DTN's named PROPHET routing works on the principle of history of encounters and transitivity (3). It is called Probabilistic routing protocol since it uses a parameter 'Delivery of Predictability'. Using Fuzzy Logic some rules will be defined and another parameter 'Energy value' will be considered to calculate the probability of delivery. With the aim of consuming fewer resources by the network and minimizing the delay in message delivery this new Fuzzy based probabilistic routing protocol has been introduced. Keywords: Delay tolerant network, Fuzzy logic, Delivery Predictability, Prophet routing protocol, Epidemic routing protocol.

Integrated Social and QoS Trust-Based Routing in Delay Tolerant Networks

We propose and analyze a class of integrated social and quality of service (QoS) trust-based routing protocols in mobile ad-hoc delay tolerant networks. The underlying idea is to incorporate trust evaluation in the routing protocol, considering not only QoS trust properties but also social trust properties to evaluate other nodes encountered. We prove that our protocol is resilient against bad-mouthing, good-mouthing and whitewashing attacks performed by malicious nodes. By utilizing a stochastic Petri net model describing a delay tolerant network consisting of heterogeneous mobile nodes with vastly different social and networking behaviors, we analyze the performance characteristics of trust-based routing protocols in terms of message delivery ratio, message delay, and message overhead against connectivity-based, epidemic and PROPHET routing protocols. The results indicate that our trust-based routing protocols outperform PROPHET and can approach the ideal performance obtainable by epidemic routing in delivery ratio and message delay, without incurring high message overhead. Further, integrated social and QoS trust-based protocols can effectively trade off message delay for a significant gain in message delivery ratio and message overhead over traditional connectivity-based routing protocols.

Fame-Based Probabilistic Routing for Delay-Tolerant Networks

One of the important technologies for the Future Internet is the delay-tolerant network, which enables data transfers even when mobile nodes are connected intermittently. Routing algorithms for a delay-tolerant network generally aim to increase the message delivery rate and decrease the number of forwarded messages in the situation of an intermittent connection. A fame-based strategy for delay-tolerant network routing is suggested in this work. The number of contacts of a node with other nodes, known as the fame degree in this work, is counted to rank the fame degree of the node. By utilizing the fame degree, the proposed routing algorithm determines the probability of forwarding the messages of a node to the contact node. Due to the characteristics of the proposed algorithm, it can be combined harmonically with the PROPHET routing algorithm. Through experiments on well-known benchmark datasets, the proposed algorithms shows better delivery rates with much lower number of forwarded messages and lower average hop counts of delivered messages compared to Epidemic, PROPHET and SimBet.

Performance Evaluation of a Power Management Scheme for Disruption Tolerant Network

Disruption tolerant network (DTN) is characterized by frequent partitions and intermittent connectivity. Power management issue in such networks is challenging. Existing power management schemes for wireless networks cannot be directly applied to DTNs because they assume the networks are well-connected. Since the network connectivity opportunities are rare, any power management scheme deployed in DTNs should not worsen the existing network connectivity. In this paper, we design a power management scheme called context-aware power management scheme (CAPM) for DTNs. Our CAPM scheme has an adaptive on period feature that allows it to achieve high delivery ratio and low delivery latency when used with Prophet, a recently proposed DTN routing scheme. Via simulations, we evaluate the performance of the CAPM scheme when used with the Prophet routing scheme in different scenarios e.g. different traffic load, node speeds and sleep patterns. Our evaluation results indicate that the CAPM scheme is very promising in providing energy saving (as high as 80%) without degrading much the data delivery performance.