Redundant Messages Research Articles

Domain-epidemic spray and forward routing algorithm of opportunistic networks

For the current opportunistic networks routing algorithms, their message arrival rate is not high and the delivery delay is large. This paper proposes a domain-epidemic spray and forward routing algorithm. The algorithm integrates redundancy and encounter prediction strategy. According to the probability of encounters between nodes, the nodes are divided into different domains. The spray and forward strategy is used between domains and the epidemic strategy is used to forward messages within a domain. Using the message confirmation mechanism and a list which is used to record the messages that have arrived to their destination, the new algorithm can effectively reduce redundant messages. Simulation results show our algorithm can effectively improve message arrival rate and reduce end-to-end delay to some extent.

BI-Filtered Forwarding: A Quasi-Optimal Routing Algorithm for Query Delivery in Wireless Sensor Networks

Abstract A quasi-optimal query propagation algorithm Bi-Filtered Forwarding (BFF) for quickly routing a query throughout a wireless sensor network is proposed in this paper. BFF is implemented in a limited flooding manner for guaranteeing quick query propagation and low message consumption in wireless sensor networks. The experimental results show that in comparison with the flooding algorithm, BFF can greatly reduce the redundant message consumption during the procedure of real time query propagation throughout a wireless sensor network.

Multiple achromatic plumage ornaments signal to multiple receivers

We investigated whether achromatic plumage traits can act as multiple ornaments in an Arctic-breeding passerine, the snow bunting (Plectrophenax nivalis). Specifically, we examine whether multiple ornaments are providing multiple differing messages, are redundant, are unreliable signals of male quality, or are aimed at different receivers. We measured plumage reflectance and pigmentation patterns made conspicuous during male inter- and intrasexual displays that advertise different plumage regions. Our results indicate that although several aspects of male plumage may have redundant messages, different body regions appear aimed at different receivers. The wings of males—displayed primarily toward females during courtship—appear to indicate a pair’s future reproductive performance. Conversely, melanin-based plumage reflectance displayed during intrasexual threat displays provides information on territory features and a male’s capacity to defend it (i.e., territory size, territory quality, testosterone levels). Taken together, we suggest that snow buntings have multiple ornaments that provide information of differential importance in inter- versus intrasexual communication. This study demonstrates that achromatic plumage traits can serve in complex communication. Key wor ds: achromatic plumage, individual quality , multiple ornaments, multiple receivers, Plectrophenax nivalis. [Behav Ecol]

Cell ID extension in femtocell environments

In this paper, we solve a cell identification problem in a femtocell environment. Wireless communication standards specify physical cell identifiers (PCIs) for user entities (UEs) to discriminate data from different cells and for networks to identify cells. However, in the densely deployed area, the number of PCIs for femtocells may not be sufficient. The scarcity of PCIs results in identification ambiguity due to duplicated PCIs in a certain area, which may result in handover failure. Using time synchronization between femtocells and macro-cells, we propose a scheme to efficiently identify cells in a femtocell environment. The proposed scheme defines the virtual cell identifier (vID) of a femtocell as the system frame number offset of the femtocell with respect to a macro-cell and differentiates femtocells with combinations of vIDs and PCIs. Our scheme can increase the number of cell identifiers up to 1024 times using even coarse local time synchronization without changing the existing physical layer specification. The improvement in cell identification resolution reduces redundant message transactions, resulting in network performance enhancement. Since our scheme demands only local time synchronization between adjacent cells, it can be applied to asynchronous as well as synchronous wireless systems. We verify the proposed scheme via simulations in various environments.

Correlations of Condition, Testosterone, and Age with Multiple Ornaments in Male House Sparrows: Patterns and Implications

Abstract. Why many animals display several different kinds of ornaments has been of recent interest in animal-communication research. Three key hypotheses have been suggested: multiple ornaments can function as (1) multiple messages (each ornament provides different information), (2) redundant messages or back-up signals (all ornaments provide the same information), and (3) unreliable signals (no information). Here we tested the signal properties of ornamental traits of male House Sparrows (Passer domesticus) to better resolve the potential information different ornaments reveal. We repeatedly measured badge size, wingbar area and color, bill color, and leg color in 170 captive males over 3 years. We found that (1) badge size and wingbar area were related to condition (to mass, tarsus length, and the interaction of both), (2) badge size, wingbar area, and bill color were related to testosterone levels, (3) all ornaments except bill color were related to age, and (4) origin had only minor effects. We concl...

에너지 효율성 향상을 위하여 방향성 메시징을 사용하는 수정된 지그비의 설계 및 구현

ZigBee is the low power, low cost and low data rate wireless personal area network(LR-WPAN) standard. The Directed-Messaging is the protocol which improves the energy efficiency through reducing the redundant message transmission by transmitting messages with directional information toward the specified sub-network area in wireless sensor network using broadcasting. In this paper, we design and implement the experimental grid sensor network using ZigBee modified by the Directed-Messaging for the energy efficiency improvement. The experimental sensor network in this paper is configured with Nano24 supporting the ADV message and the routing management module modified to use the directional information. The energy efficiency improvement of the experimental sensor-network by evaluating the experimental results according to transmitting ADV message.

An Adaptive Randomized Fault Detection Service

Fault detection is a fundamental element for management, replication, load balancing, and other services of large-scale distributed systems. But the fault detection services in such systems scale badly in the number of members that are being monitored. This paper describes a new protocol named Adaptive Randomized Gossip-based Fault Detection service (ARGoFD) which based on gossiping that does scale well and provides timely detection. We gave out a detailed description of the protocol and analyzed its main algorithms. At last we did the comparison experiments. The experiment result shows that ARGoFD could effectively reduce the redundant messages amount and increase the detection convergence rate.

Removing Redundant Messages in N-ary BnB-ADOPT

This note considers how to modify BnB-ADOPT, a well-known algorithm for optimally solving distributed constraint optimization problems, with a double aim: (i) to avoid sending most of the redundant messages and (ii) to handle cost functions of any arity. Some of the messages exchanged by BnB-ADOPT turned out to be redundant. Removing most of the redundant messages increases substantially communication efficiency: the number of exchanged messages is - in most cases - at least three times fewer (keeping the other measures almost unchanged), and termination and optimality are maintained. On the other hand, handling n-ary cost functions was addressed in the original work, but the presence of thresholds makes their practical usage more complex. Both issues - removing most of the redundant messages and efficiently handling n-ary cost functions - can be combined, producing the new version BnB-ADOPT+. Experimentally, we show the benefits of this version over the original one.

The detection and defence of DoS attack for wireless sensor network

Due to the limitations of energy, computation and storage for sensors etc, although the wireless sensor networks (WSNs) have been widely deployed in many applications, it is a critical challenge to present the effective and lightweight security protocol to prevent various attacks for WSN, especially for the denial of service (DoS) attack. Normally, the adversaries compromise sensors and launch the DoS attack by replaying redundant messages or making overdose of fake messages. In this paper, we design a novel message observation mechanism (MoM) to detect and defense the DoS attack. Based on the spatiotemporal correlation, MoM utilizes the similarity function to identify the content attack as well as the frequency attack. And then the MoM adopts rekey and reroute countermeasures to isolate the malicious node. The security analysis shows that our solution can not only detect and defense the DoS attack but also can reduce the energy consumption.

An optimized strategy for update path selection in unstructured P2P networks

With the growth of P2P file sharing systems, people are no longer satisfied with the sharing of the read-only and static files, and thus the systems with mutually writable and dynamic files have emerged, resulting in the replica inconsistency problem. To maintain the replica consistency, too many update messages need to be redundantly propagated due to the lack of the sharing of globally updated path information in the existing strategies. To address this problem, we propose an optimized strategy for update path selection, which makes the nodes share the update path information by using clone, variation and crossover operations for the update paths. We also present a repeated update strategy to cope with the churn problem so as to maintain replica consistency as far as possible even if some nodes temporarily leave the network. The simulation results show that our strategy can significantly reduce the number of the redundant update messages without lowering the message coverage, thus improving the availability of the unstructured P2P networks.

Structure-free message aggregation and routing in traffic information system (SMART)

In a VANET (Vehicular Ad-Hoc Network) environment, it is highly probable that multiple nodes detect and report common events. Hence, elimination of redundant messages can help in efficient bandwidth usage. Data aggregation has also been identified as another potential tool to address broadcast storm in VANETs. Though many aggregation and in-network filtering schemes have been proposed, few studies have been done to combine the two approaches in a structured fashion in order to reap the full benefits.In this work, we have shown how our proposed SMART protocol utilises the data aggregation tool in conjunction with message fragmentation, to address the prevailing challenge of vehicular networks—efficient bandwidth usage. The data is broken down into fragments and subsequently analysed, thus resulting in the elimination of redundant data than simply suppressing the transmission of duplicate data. The data received at every node is compared, analysed and stored into a well-organised data structure for faster and efficient look-up, thus transforming the network into a multi-level filtering system. Our SMART protocol is an efficient and scalable data aggregation scheme that achieves information dissemination without incurring any overhead of constructing a structure. As a proof of concept, we have shown that the SMART protocol improves efficiency in VANET communication by restricting the transmission of 75–80% redundant data.

K-최단 분리 경로 배정을 적용한 장애 복구형 선박 백본 네트워크의 성능 평가

The concept of k-shortest disjoint paths is considered important because the establishment of primary and backup forwarding paths exploiting shorter distance and faster propagation time is a dominant consideration for the design of a survivable backbone network. Therefore, we need to evaluate how well the concept of k-shortest disjoint paths is exploited for the design of a survivable ship backbone network considering the international standard related to ship backbone networks, the IEC61162-410 standard specifying how to manage redundant message transmissions among ship devices. Performance evaluations are conducted in terms of following objective goals: link capacity, hop and distance of primary and backup paths, even distribution of traffic flows, restoration time of backup forwarding paths, and physical network topology connectivity.

Provably convertible multi-authenticated encryption scheme for generalized group communications

In 2008, Wu et al. proposed a convertible multi-authenticated encryption (CMAE) scheme based on discrete logarithms. To improve the computational efficiency of Wu et al.’s scheme, Tsai proposed another CMAE scheme without using message redundancy. These CMAE schemes, however, might be inadequate for group-oriented applications. In the same year, Chang presented a CMAE scheme using message redundancy for group communications [published in Information Sciences 178 (17) (2008) 3426–3434]. In his scheme, multiple signers of the same group can cooperate with each other to generate a valid authenticated encryption signature for a designated verifying group with access structured multiple verifiers. In this paper, we propose a new convertible multi-authenticated encryption scheme without using message redundancy for generalized group communications. Multiple signers of the signing group can cooperate with each other to generate a valid authenticated encryption signature for a verifying group with access structured multiple verifiers. The verifiers in the same access structure can cooperatively recover and verify the signing group’s signature. In case of a later dispute, any participant verifier can convert the authenticated encryption signature into an ordinary one. As compared with previous works, our proposed scheme is more efficient in terms of computational efforts and communication overheads.

Pulp: An adaptive gossip-based dissemination protocol for multi-source message streams

Gossip-based protocols provide a simple, scalable, and robust way to disseminate messages in large-scale systems. In such protocols, messages are spread in an epidemic manner. Gossiping may take place between nodes using push, pull, or a combination. Push-based systems achieve reasonable latency and high resilience to failures but may impose an unnecessarily large redundancy and overhead on the system. At the other extreme, pull-based protocols impose a lower overhead on the network at the price of increased latencies. A few hybrid approaches have been proposed—typically pushing control messages and pulling data—to avoid the redundancy of high-volume content and single-source streams. Yet, to the best of our knowledge, no other system intermingles push and pull in a multiple-senders scenario, in such a way that data messages of one help in carrying control messages of the other and in adaptively adjusting its rate of operation, further reducing overall cost and improving both on delays and robustness. In this paper, we propose an efficient generic push-pull dissemination protocol, Pulp, which combines the best of both worlds. Pulp exploits the efficiency of push approaches, while limiting redundant messages and therefore imposing a low overhead, as pull protocols do. Pulp leverages the dissemination of multiple messages from diverse sources: by exploiting the push phase of messages to transmit information about other disseminations, Pulp enables an efficient pulling of other messages, which themselves help in turn with the dissemination of pending messages. We deployed Pulp on a cluster and on PlanetLab. Our results demonstrate that Pulp achieves an appealing trade-off between coverage, message redundancy, and propagation delay.

차량 간 통신 환경에서 효과적인 위험 경고 메시지 전송 방안

In this paper, we propose an algorithm to improve collision avoidance in Vehicle-to-Vehicle (V2V) networks based on IEEE 802.11p. Since IEEE 802.11p adopts CSMA/CA as a multiple access scheme and an emergency warning message (EWM) is delivered to behind vehicles in a multi-hop manner, due to transmission collision, the more vehicles in the vehicle chain results in a longer delay. The longer delay increases the possibility of a rear-end collision. In order to ensure message reception with low latency, we consider implicit acknowledgement of a broadcasted EWM message and propose an algorithm to reduce redundant message transactions, called Two-Way Implicit Acknowledgement (TWIA). By simulations, we show that our proposed algorithm can reduce the latency until the last car receives the message by 9% and the success rate every car receives the message within 0.7sec by 12% at 100 fixed-number-of-car environment.

P2P Model Based on Isolated Broadcast Domains

Resource location is the most important issue for Peer-to-Peer (P2P) system and flooding is the fundamental mechanism for unstructured P2P systems. Redundant messages will exponential growth with flooding scope increasing which severely influences the scalability of the system. In this paper, a new P2P model based on isolated broadcast domains is given to reduce the amount of redundant messages by limiting the radius of messages transmitted. Analysis and experiments show that this model can guarantee coverage of nodes and significantly reduce the amount of redundant messages generated.

Towards efficient and practical network coding in delay tolerant networks

Network coding techniques offer an emerging solution to efficient data transmission in Delay Tolerant Networks (DTN). To date, abundant techniques have been developed on exploiting network coding in DTN, however, most of them bring additional overhead due to the extra coded message redundancy. In this paper, we analyze the coded message redundancy issue, and then propose NTC, an efficient network coding scheme for DTN. In NTC, a novel metric named “redundancy ratio” is introduced within the anti-entropy message exchange process. We also discuss the design and implementation of practical NTC in detail. To evaluate the performance of our proposed NTC scheme, we implement NTC in ONE, the current state-of-the-art simulator for DTN. Simulation results show that, comparing with existing schemes, our proposed NTC scheme has significant advantages in enhancing the message delivery ratio and reducing the transmission overhead.

GrAnt: Inferring best forwarders from complex networks’ dynamics through a greedy Ant Colony Optimization

This paper presents a new prediction-based forwarding protocol for complex and dynamic delay tolerant networks (DTNs). The proposed protocol is called GrAnt (Greedy Ant), as it uses the Ant Colony Optimization (ACO) metaheuristic with a greedy transition rule. This allows GrAnt to select the most promising forwarder nodes or allow for the exploitation of previously found good paths. The main motivation for using ACO is to take advantage of its population-based search and the rapid adaptation of its learning framework. Considering data from heuristic functions and pheromone concentration, the GrAnt protocol includes three modules: routing, scheduling, and buffer management. To the best of our knowledge, this is the first unicast protocol that employs a greedy ACO and that (1) infers best promising forwarders from nodes’ social connectivity, (2) determines the best paths a message must follow to eventually reach its destination while limiting message replications and droppings, and (3) performs message transmission scheduling and buffer space management. GrAnt is compared to the Epidemic and PROPHET protocols in two different mobility scenarios: one activity-based scenario (Working Day) and another based on Points of Interest. Simulation results obtained by the ONE simulator show that, in both scenarios, GrAnt achieves a higher delivery ratio, lower message redundancy, and fewer dropped messages than Epidemic or PROPHET.

A routing protocol suitable for backhaul access in wireless mesh networks

This work proposes the Wireless-mesh-network Proactive Routing (WPR) protocol for wireless mesh networks, which are typically employed to provide backhaul access. WPR computes routes based on link states and, unlike current routing protocols, it uses two algorithms to improve communications in wireless mesh networks taking advantage of traffic concentration on links close to the network gateways. WPR introduces a controlled-flooding algorithm to reduce routing control overhead by considering the network topology similar to a tree. The main goal is to improve overall efficiency by saving network resources and avoiding network bottlenecks. In addition, WPR avoids redundant messages by selecting a subset of one-hop neighbors, the AMPR (Adapted MultiPoint Relay), needed to reach all two-hop ones. We first analyze the proposed algorithms compared with the algorithms used by OLSR for the same tasks in terms of running time, optimality, and number of routing messages. Results show that the algorithms proposed by WPR are more efficient than the algorithms used by OLSR in running time and number of routing messages. In addition, we also perform simulations to evaluate the performance of WPR. Results reveal that the aggregated throughput of WPR outperforms OLSR by up to 27% using a combination of web and backbone internal traffic despite our design assumption of traffic convergence toward gateways.

Efficient broadcasting using packet history in mobile ad hoc networks

Broadcasting is a key component of several networking mechanisms in mobile ad hoc networks. However, its traditional implementation suffers from resource consumption caused by message redundancy. Several efficient algorithms have been proposed to tackle this problem. Among them, the class of algorithms that construct on-demand a connected dominating set, known as dominant pruning, yields an improved performance. Dominant pruning algorithms capitalise on neighbourhood information and the previous hop of the broadcast message in order to minimise the set of nodes that forward a message. The proposed algorithm makes the observation that all the nodes, visited by a broadcast message, may be exploited in order to minimise the cost of broadcasting. The analysis of the proposed algorithm as well as extensive simulation results confirm the rationale behind the proposed approach and prove the performance gains.