Narrowband delay tolerant protocols for WSN applications. Characterization and selection guide

This article focuses on delay tolerant protocols for Wireless Sensor Network (WSN) applications, considering both established and new protocols. We obtained a comparison of their characteristics by implementing all of them on an original platform for network simulation, and by testing their behavior on a common test-bench. Thereafter, matching the requirements linked to each application with the performances achieved in the test-bench, allowed us to define an application oriented protocol selection guide

Evaluating Mobility Pattern Space Routing for DTNs

Because a delay tolerant network (DTN) can often be partitioned, the problem of routing is very challenging. However, routing benefits considerably if one can take advantage of knowledge concerning node mobility. This paper addresses this problem with a generic algorithm based on the use of a high-dimensional Euclidean space, that we call MobySpace, constructed upon nodes' mobility patterns. We provide here an analysis and the large scale evaluation of this routing scheme in the context of ambient networking by replaying real mobility traces. The specific MobySpace evaluated is based on the frequency of visit of nodes for each possible location. We show that the MobySpace can achieve good performance compared to that of the other algorithms we implemented, especially when we perform routing on the nodes that have a high connection time. We determine that the degree of homogeneity of mobility patterns of nodes has a high impact on routing. And finally, we study the ability of nodes to learn their own mobility patterns.Comment: IEEE INFOCOM 2006 preprin

Effective Dissemination of Presence Information in Highly Partitioned Mobile Ad Hoc Networks

Presence technology enables users of an instant messaging (IM) system to determine if their contacts are online and ready to communicate. In this paper, we propose an effective approach for the proactive dissemination of frequently changing presence information in highly partitioned mobile, wireless networks with IEEE 802.11 technology. Although communication techniques for intermittently connected networks have been extensively studied in the field of delay tolerant networking, the fact that presence information is highly delay sensitive requires a thorough revision of these techniques. To this end, we use discrete-event simulation based on a high-level stochastic model of the IM system to compare different approaches for disseminating presence information in terms of sustained consistency (i.e., fraction of time presence information is in a coherent state) and traffic requirements. Building upon the outcome of the simulation study, we propose the system for presence information exchange by epidemic dissemination (SPEED). Results of a detailed ns-2 simulation study show that SPEED outperforms an approach based on optimized flooding by up to 20% in terms of sustained consistency for low node density and saves up to 48% of control traffic for medium to high node density

Delay-Tolerant, Low-Power Protocols for Large Security-Critical Wireless Sensor Networks

This paper reports the analysis, implementation, and experimental testing of a delay-tolerant and energy-aware protocol for a wireless sensor node, oriented to security applications. The solution proposed takes advantages from different domains considering as a guideline the low power consumption and facing the problems of seamless and lossy connectivity offered by the wireless medium along with very limited resources offered by a wireless network node. The paper is organized as follows: first we give an overview on delay-tolerant wireless sensor networking (DTN); then we perform a simulation-based comparative analysis of state-of-the-art DTN approaches and illustrate the improvement offered by the proposed protocol; finally we present experimental data gathered from the implementation of the proposed protocol on a proprietary hardware node

Tracking User-movement in Opportunistic Networks to Support Distributed Query-response During Disaster Management

AbstractEffective communication amongst diverse rescue and relief workers is a primary requirement in any disaster management. Since pre-existing communication infrastructure may not be available, the Opportunistic Network framework provides a potential platform for information communication, where individual smart-phones of rescue and relief workers (the nodes) spread across an environment form a disjoint, peer-to-peer network. Here, a source node communicates with a destination node following hop-by-hop, store-wait-forward cycle, since an end-to-end route connecting them never exists. Also, due to mobility and disconnectedness, nodes have scarce or no knowledge about the network topology. However, in the context of disaster management, in order to evaluate the situation, rescue and relief workers often need to generate different field-related queries and the response to those queries must come from other workers in the field. Since source node (generating the query) is not aware of the location of destination node (answering the query) and all nodes are mobile, it is difficult to implement a query-response mechanism. This paper proposes and evaluates a distributed query-response mechanism that enables any node to track approximate location of other rescue and relief workers, which is turn helps to handle query-response operations

Enhanced Data Delivery Framework for Dynamic Information-Centric Networks (ICNs)

Abstract-In this paper, we present an Enhanced 2-Phase Data Delivery (E2-PDD) framework for Information-Centric Networks (ICNs), focusing on efficient content access and distribution as opposed to mere communication between data consumers and publishers. We employ an approach of growing eminence, where requests are initiated by consumers seeking particular services that are data-dependent. High-level Controllers (HCs) receive the consumers' requests and issue queries to a multitude of data publishers. The publishers in our topology include a wide variety of ubiquitous nodes that could be either stationary or mobile, operating under different protocols. In order to consider fundamental challenges in ICNs such as node mobility and data disruption, our E2-PDD framework employs Low-level Controllers (LCs) that act as moderators between the HCs and the data publishers, executing data queries for a top tier and replying back with a set of candidate rendezvous points obtained from a bottom tier. The HCs maximize selection based on the nearest rendezvous. Extensive simulation results have been used to evaluate our E2-PDD framework in terms of key performance metrics in ICNs viz., average in-network delay, and publisher load, given different mobility pause time durations and data consumers' densities

SAROS: A social-aware opportunistic forwarding simulator

Many applications are being developed to leverage the popularity of mobile opportunistic networks. However, building adaptive testbeds can be costly and challenging. This challenge motivates the need for effective opportunistic network simulators to provide a variety of opportunistic environment setups, and evaluate proposed applications and protocols with a comprehensive set of metrics. This paper presents SAROS, a simulator of opportunistic networking environments with a variety of interest distributions, power consumption distributions, imported real traces, and social network integration. The simulator provides a wide variety of evaluation metrics that are not offered by comparable simulators. Finally, SAROS also implements several opportunistic forwarding algorithms ranging from social-oblivious algorithms to interest and power-aware social-based algorithms

Priority-based message forwarding and query processing in opportunistic wireless sensor network

提出了机会无线传感器网络中一种基于查询优先级的查询分发和处理(PbQ)算法。算法根据用户定义的查询优先级合理选取消息转发的中间节点,并控制查询消息的转发和拷贝量;同时,动态地调整查询消息的优先级,使得查询结果能快速回传到查询发起者并清理网络中查询的残留消息,避免了不必要的消息传输并提高查询处理的整体效用。模拟实验表明PbQ算法能有效提高机会网络中查询处理的成功率,降低查询的开销和时间延迟。A priority-based algorithm called PBQ was proposed for the query forwarding and processing in opportunistic wireless sensor network.Through the user-defined query priorities, the proposed algorithm properly selects the relay nodes and controlls the forwarding and the amount of messages.Meanwhile, the query priorities were adjusted dynamically so that the query results could be forwarded back to the source node of the query quickly and the residual query request messages could be cleaned up from the network, saving lots of unnecessary transmissions and improving the overall utility of query processing.Simulating results show that PBQ could effectively improve the success rate of queries, and reduce the cost and delay of query processing in opportunistic wireless sensor network.国家自然科学基金资助项目(61202012;61303004); 福建省自然科学基金资助项目(2011J05156;2013J05099); 中央高校基本科研业务费专项基金资助项目(2012121030)~