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Routing design for bandwidth-aware multi-channel wirelessmesh networks
多信道无线网状网带宽有效的路由机制设计

XIANG Kai,ZENG Yuan-yuan,
项 慨
,曾园园

计算机应用研究 , 2012,
Abstract: This paper presented a distributed bandwidth-aware routing protocol based on multi-channel wireless mesh networks by utilizing admission control. The protocol used distributed link schedule to prevent interference and guaranteed enough bandwidth for link flow by slot assignment schemes. It made NS-2 simulations to test the protocol. The results show that this protocol achieves much better performance, it can effectively provide bandwidth guaranteed path according to connection requests.
Intersection-Aware Channel Assignment and Routing in Multi-Channel Multi-Hop Wireless Networks with a Single Transceiver
Huang Chuanhe,Cheng Yong,Yang Ling,Shi Wenming,Zhou Hao
International Journal of Distributed Sensor Networks , 2009, DOI: 10.1080/15501320802520563
Abstract: This article proposes an intersection-aware channel assignment and routing protocol for wireless ad hoc networks with a single transceiver. This protocol increases the network capacity of an IEEE 802.11 network by exploiting frequency diversity. Using the proposed protocol, multiple communications can simultaneously take place in a region without interfering with each other. However, it must avoid a multi-channel hidden terminal problem for designing channel assignment and routing protocol. This paper considers issues regarding multiple channels at the network layer, assuming a single channel MAC protocol such as IEEE 802.11 DCF. Also, the proposed protocol assumes that each node in the network is equipped with a single transceiver. This set of assumptions is very practical, because most devices have a single wireless card implementing the IEEE 802.11 DCF protocol. Each node uses modular exponentiation congruence to represent the channel schedule, which assures that each pair of nodes has common channels for communication in every cycle. Each node switches across channels in such a manner that each pair of nodes works on the same channel when they desire to communicate; otherwise they work on a different channel, and hence do not interfere with each other. However, for the intersecting node, there is no benefit in using single radio multiple channels since the capacity around the intersection node can at most be O (W), W is the link capacity, regardless of the number of channels. The protocol lets the intersecting node always work on the same channel whereas the nonintersecting node can work on different channels.
CROR: Coding-Aware Opportunistic Routing in Multi-Channel Cognitive Radio Networks  [PDF]
Xiaoxiong Zhong,Yang Qin,Yuanyuan Yang,Li Li
Computer Science , 2015,
Abstract: Cognitive radio (CR) is a promising technology to improve spectrum utilization. However, spectrum availability is uncertain which mainly depends on primary user's (PU's) behaviors. This makes it more difficult for most existing CR routing protocols to achieve high throughput in multi-channel cognitive radio networks (CRNs). Inter-session network coding and opportunistic routing can leverage the broadcast nature of the wireless channel to improve the performance for CRNs. In this paper we present a coding aware opportunistic routing protocol for multi-channel CRNs, cognitive radio opportunistic routing (CROR) protocol, which jointly considers the probability of successful spectrum utilization, packet loss rate, and coding opportunities. We evaluate and compare the proposed scheme against three other opportunistic routing protocols with multichannel. It is shown that the CROR, by integrating opportunistic routing with network coding, can obtain much better results, with respect to throughput, the probability of PU-SU packet collision and spectrum utilization efficiency.
Centralized Quasi-Static Channel Assignment for Multi-Radio Multi-Channel Wireless Mesh Networks  [PDF]
Juan REN, Zhengding QIU
Wireless Sensor Network (WSN) , 2009, DOI: 10.4236/wsn.2009.12016
Abstract: Employing multiple channels in wireless multihop networks is regarded as an effective approach to increas-ing network capacity. This paper presents a centralized quasi-static channel assignment for multi-radio multi-channel Wireless Mesh Networks (WMNs). The proposed channel assignment can efficiently utilize multiple channels with only 2 radios equipped on each mesh router. In the scheme, the network end-to-end traffics are first modeled by probing data at wireless access points, and then the traffic load between each pair of neighboring routers is further estimated using an interference-aware estimation algorithm. Having knowledge of the expected link load, the scheme assigns channels to each radio with the objective of mini-mizing network interference, which as a result greatly improves network capacity. The performance evalua-tion shows that the proposed scheme is highly responsive to varying traffic conditions, and the network per-formance under the channel assignment significantly outperforms the single-radio IEEE 802.11 network as well as the 2-radio WMN with static 2 channels.
Joint Design of Congestion Control Routing With Distributed Multi Channel Assignment in Wireless Mesh Networks  [PDF]
K. Valarmathi,N. Malmurugan
Computer Science , 2010,
Abstract: In Wireless Mesh Networks (WMN), a channel assignment has to balance the objectives of maintaining connectivity and increasing the aggregate bandwidth. The main aim of the channel assignment algorithm is to assign the channels to the network interfaces, from the given expected load on each virtual link. From the existing work done so far, we can examine that there is no combined solution of multi-channel assignment with routing and congestion control. In this paper, we propose a congestion control routing protocol along with multi-channel assignment. We use a traffic aware metric in this protocol in order to provide quality of service. The proposed protocol can improve the throughput and channel utilization to very high extent because it provides solution for multi-channel assignment and congestion control. The proposed algorithm assigns the channels in a way that, congestion is avoided and co-channel interference levels among links with same channel are reduced. By our simulation results in NS2, we show that the proposed protocol attains high throughput and channel utilization along with reduced latency.
Coefficient of Restitution based Cross Layer Interference Aware Routing Protocol in Wireless Mesh Networks  [PDF]
Sarasvathi V,Snehanshu Saha,N. Ch. S. N. Iyengar,Mahalaxmi Koti
Computer Science , 2015,
Abstract: In Multi-Radio Multi-Channel (MRMC) Wireless Mesh Networks (WMN), Partially Overlapped Channels (POC) has been used to increase the parallel transmission. But adjacent channel interference is very severe in MRMC environment; it decreases the network throughput very badly. In this paper, we propose a Coefficient of Restitution based Cross layer Interference aware Routing protocol (CoRCiaR) to improve TCP performance in Wireless Mesh Networks. This approach comprises of two-steps: Initially, the interference detection algorithm is developed at MAC layer by enhancing the RTS/CTS method. Based on the channel interference, congestion is identified by Round Trip Time (RTT) measurements, and subsequently the route discovery module selects the alternative path to send the data packet. The packets are transmitted to the congestion free path seamlessly by the source. The performance of the proposed CoRCiaR protocol is measured by Coefficient of Restitution (COR) parameter. The impact of the rerouting is experienced on the network throughput performance. The simulation results show that the proposed cross layer interference aware dynamic routing enhances the TCP performance on WMN. Keywords: Coefficient of Restitution, Wireless Mesh Networks, Partially Overlapped Channels, Round Trip Time, Multi-Radio, Multi-Channel.
Two-stage coordination multi-radio multi-channel mac protocol for wireless mesh networks  [PDF]
Bingxuan Zhao,Shigeru Shimamoto
Computer Science , 2011,
Abstract: Within the wireless mesh network, a bottleneck problem arises as the number of concurrent traffic flows (NCTF) increases over a single common control channel, as it is for most conventional networks. To alleviate this problem, this paper proposes a two-stage coordination multi-radio multi-channel MAC (TSC-M2MAC) protocol that designates all available channels as both control channels and data channels in a time division manner through a two-stage coordination. At the first stage, a load balancing breadth-first-search-based vertex coloring algorithm for multi-radio conflict graph is proposed to intelligently allocate multiple control channels. At the second stage, a REQ/ACK/RES mechanism is proposed to realize dynamical channel allocation for data transmission. At this stage, the Channel-and-Radio Utilization Structure (CRUS) maintained by each node is able to alleviate the hidden nodes problem; also, the proposed adaptive adjustment algorithm for the Channel Negotiation and Allocation (CNA) sub-interval is able to cope with the variation of NCTF. In addition, we design a power saving mechanism for the TSC-M2MAC to decrease its energy consumption. Simulation results show that the proposed protocol is able to achieve higher throughput and lower end-to-end packet delay than conventional schemes. They also show that the TSC-M2MAC can achieve load balancing, save energy, and remain stable when the network becomes saturated.
TWO-STAGE COORDINATION MULTI-RADIO MULTI-CHANNEL MAC PROTOCOL FOR WIRELESS MESH NETWORKS  [PDF]
Bingxuan Zhao,Shigeru Shimamoto
International Journal of Computer Networks & Communications , 2011,
Abstract: Within the wireless mesh network, a bottleneck problem arises as the number of concurrent traffic flows(NCTF) increases over a single common control channel, as it is for most conventional networks. Toalleviate this problem, this paper proposes a two-stage coordination multi-radio multi-channel MAC(TSC-M2MAC) protocol that designates all available channels as both control channels and datachannels in a time division manner through a two-stage coordination. At the first stage, a load balancingbreadth-first-search-based vertex coloring algorithm for multi-radio conflict graph is proposed tointelligently allocate multiple control channels. At the second stage, a REQ/ACK/RES mechanism isproposed to realize dynamical channel allocation for data transmission. At this stage, theChannel-and-Radio Utilization Structure (CRUS) maintained by each node is able to alleviate the hiddennodes problem; also, the proposed adaptive adjustment algorithm for the Channel Negotiation andAllocation (CNA) sub-interval is able to cope with the variation of NCTF. In addition, we design a powersaving mechanism for the TSC-M2MAC to decrease its energy consumption. Simulation results show thatthe proposed protocol is able to achieve higher throughput and lower end-to-end packet delay thanconventional schemes. They also show that the TSC-M2MAC can achieve load balancing, save energy,and remain stable when the network becomes saturated.
Interference-Aware Channel Assignment for Maximizing Throughput in WMN  [PDF]
Vinay Kapse,Urmila Shrawankar
Computer Science , 2013,
Abstract: Wireless Mesh network (WMN) is dynamically self-organizing and self-configured, with the nodes in the network automatically establishing an ad-hoc network and maintaining the mesh connectivity. The ability to use multiple-radios and multiple channels can be cashed to increase aggregate throughput of wireless mesh network. Thus the efficient use of available interfaces and channels without interference becomes the key factor. In this paper we propose, interference aware clustered based channel assignment schemes which minimizes the interference and increases throughput. In our proposed scheme we have given priority to minimize interference from nearby mesh nodes in interference range than maximizing channel diversity. We simulated our proposed work using NS-3 and results show that our scheme improves network performance than BFSCA and Distributed Greedy CA.
Online Multi-Coloring with Advice  [PDF]
Marie G. Christ,Lene M. Favrholdt,Kim S. Larsen
Computer Science , 2014,
Abstract: We consider the problem of online graph multi-coloring with advice. Multi-coloring is often used to model frequency allocation in cellular networks. We give several nearly tight upper and lower bounds for the most standard topologies of cellular networks, paths and hexagonal graphs. For the path, negative results trivially carry over to bipartite graphs, and our positive results are also valid for bipartite graphs. The advice given represents information that is likely to be available, studying for instance the data from earlier similar periods of time.
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