We consider the problem of maximizing the multicast lifetime in wireless ad hoc networks with directional *** a simulation study,we have discovered that the existing distributed algorithm for such optimization problem...
详细信息
We consider the problem of maximizing the multicast lifetime in wireless ad hoc networks with directional *** a simulation study,we have discovered that the existing distributed algorithm for such optimization problem may generate considerable number of control messages to build up a longest-lived multicast tree in large-scale *** may prohibit them from being used directly in ad hoc networks with limited energy and *** this paper,we would like to investigate some mechanisms to improve the communication complexity of the distributed *** explore some important properties of this optimization problem from a graph theory perspective and derive several localized operations that are especially beneficial to the resource-constrained (*** energy,memory,and computation capabilities) wireless ad hoc *** localized operations have low complexity for both memory and computation requirements at each *** simulation results show that the proposed localized operations would allow our distributed algorithms to achieve an expected linear communication complexity.
Determining the "weakest" failure detectors is a central topic in solving many agreement problems such as Consensus, Non-Blocking Atomic Commit and Election in asynchronous distributed systems. So far, this ...
详细信息
Determining the "weakest" failure detectors is a central topic in solving many agreement problems such as Consensus, Non-Blocking Atomic Commit and Election in asynchronous distributed systems. So far, this has been studied extensively for several such fundamental problems. It is stated that Perfect Failure Detector P is the weakest failure detector to solve the Election problem with any number of faulty processes. In this paper, we introduce Modal failure detector M and show that to solve Election, M is the weakest failure detector to solve election when the number of faulty processes is less than [n/2]. We also show that it is strictly weaker than P.
This paper deals with the problem of medium access control (MAC)-layer fair power control in a wireless mesh network with an established network topology. The notion of MAC layer fairness is defined along similar line...
详细信息
This paper deals with the problem of medium access control (MAC)-layer fair power control in a wireless mesh network with an established network topology. The notion of MAC layer fairness is defined along similar lines as end-to-end fairness for elastic traffic, except that instead of end-to-end flows, MAC- layer flows are considered, being that one hop flows between neighboring nodes. In this paper, we identify a class of utility functions of link rates that allows for a convex problem formulation. The convexity property is a key prerequisite for implementing power control algorithms in practice. We present a novel distributed algorithmic solution to the power control problem based on gra dient-projection methods, prove its global convergence, and provide sufficient conditions for a geometric convergence rate. The main novelty of our scheme lies in the use of the so-called adjoint network in such a way that each transmitter can estimate its current update direction from the received signal power. This mitigates the problem of global coordination of the transmitters when carrying out gradient-projection algorithms in distributed wireless networks. The price for this are possible estimation errors so that the proposed scheme is analyzed within the framework of stochastic approximation.
A distributed adaptive rate system for wireless packet networks is proposed. Compared to the centralized adaptive rate system that needs to know the packet retransmission probability to maximize the throughput, this s...
详细信息
A distributed adaptive rate system for wireless packet networks is proposed. Compared to the centralized adaptive rate system that needs to know the packet retransmission probability to maximize the throughput, this system need not know the packet retransmission probability in advance and can achieve the optimal adaptive rate system that maximizes the throughput for wireless packet networks.
A distributed joint routing and medium access control (MAC) algorithm is proposed for lifetime maximization of wireless sensor networks. By adopting the flow contention graph model and the resulting MAC constraints, t...
详细信息
A distributed joint routing and medium access control (MAC) algorithm is proposed for lifetime maximization of wireless sensor networks. By adopting the flow contention graph model and the resulting MAC constraints, the problem can be formulated into a linear programming problem, which can be solved distributively using dual decomposition. However, the message passing overhead of such a solution is high, since the information exchange must occur among the interfering links as well as the communicating links. In this work, the MAC layer constraints are relaxed in the form of a penalty function, which facilitates distributed optimization using only the collision statistic that each node can accumulate essentially at no extra cost. The resulting algorithm solves a convex optimization problem by a distributed primal-dual approach, where the network layer problem is solved in the dual domain, and the MAC layer problem is solved in the primal domain.
Wireless sensor network consists of large number of sensor nodes with limited battery power, which are randomly deployed over certain area for several applications. Due to limited energy resource of sensors, each of t...
详细信息
Wireless sensor network consists of large number of sensor nodes with limited battery power, which are randomly deployed over certain area for several applications. Due to limited energy resource of sensors, each of them should minimize the energy consumption to prolong the network lifetime. In this paper, a distributed algorithm for the multi-hop wireless sensor network is proposed to construct a novel energy efficient tree topology, without having location information of the nodes. Energy conservation of the nodes is accomplished by controlling transmission power of the nodes. Besides, maintenance of the network topology due to energy scarcity of the gateway nodes is also proposed in the protocol. Simulation results show that our distributed protocol can achieve energy conservation up to an optimum level similar to the centralized algorithm that we have considered and can extend the network lifetime as compared to other distributed algorithms without any power control. (C) 2007 Elsevier B.V. All rights reserved.
Routing is a critical issue in networking *** basic problem of QoS routing is to satisfy some network parameters constrained of many conditions which is a NP-complete problem and QoS parameters are nondeterministic ev...
详细信息
Routing is a critical issue in networking *** basic problem of QoS routing is to satisfy some network parameters constrained of many conditions which is a NP-complete problem and QoS parameters are nondeterministic even *** practical heuristic algorithms are researched to solve such a *** on partheno-GA with binary coding,the network model and mathematical model of QoS routing are constructed,and the distributed QoS routing algorithm is put *** algorithm can be easily implemented through dividing the giant and complex network into some *** simulation result shows that the algorithm can meet increasing daily QoS requirements on Internet,and improve performance more 10 times in time and space complexity compared with the source routing algorithms.
Serial data aggregation ensures minimal energy consumption since only one sensor initiates the algorithm and each sensor communicates only once with its successor. But it is difficult in a real scenario (essentially d...
详细信息
Serial data aggregation ensures minimal energy consumption since only one sensor initiates the algorithm and each sensor communicates only once with its successor. But it is difficult in a real scenario (essentially distributed) to synchronize all sensors to collaborate. In this paper we propose a linear distributed algorithm to aggregate data and we simulate it for different scenarios using the ns2 network simulator. We conclude that the proposed algorithm consume energy in a uniform way.
Two distributed algorithms DMMT-OA and DMMT-DA have been recently proposed to maximize the multicast lifetime for directional communications in wireless ad-hoc networks. The experimental results have shown their super...
详细信息
ISBN:
(纸本)97830540726050
Two distributed algorithms DMMT-OA and DMMT-DA have been recently proposed to maximize the multicast lifetime for directional communications in wireless ad-hoc networks. The experimental results have shown their superior performance than other centralized algorithms;however, their theoretical performance in terms of approximation ratio is still unknown. In this paper, we use graph theoretic approach to derive the approximation ratio for both algorithms. Furthermore, we have discovered by the first time that both ratios are bounded by a constant number.
Peer-to-Peer (P2P) systems are currently receiving considerable interest. However, as experience with P2P networks shows, the selfish behaviors of peers may lead to serious problems of P2P network, such as free-riding...
详细信息
ISBN:
(纸本)9780819469335
Peer-to-Peer (P2P) systems are currently receiving considerable interest. However, as experience with P2P networks shows, the selfish behaviors of peers may lead to serious problems of P2P network, such as free-riding and white-washing. In order to solve these problems, there are increasing considerations on reputation system design in the study of P2P networks. Most of the existing works is concerning probabilistic estimation or social networks to evaluate the trustworthiness for a peer to others. However, these models can not be efficient all the time. In this paper, our aim is to provide a general mechanism that can maximize P2P networks social welfare in a way of Vickrey-Clarke-Groves family, while assuming every peer in P2P networks is rational and selfish, which means they only concern about their own outcome. This mechanism has some desirable properties using an O(n) algorithm: (1) incentive compatibility, every peer truly report its connection type;(2) individually rationality;and (3) fully decentralized, we design a multiple-principal multiple-agent model, concerning about the service provider and service requester individually.
暂无评论