Wireless mesh network

About: Wireless mesh network is a research topic. Over the lifetime, 13600 publications have been published within this topic receiving 221035 citations. The topic is also known as: WMN.

EMPOWER: a network emulator for wireline and wireless networks

Abstract: The increasing need of protocol development environments and network performance evaluation tools gives rise to the research of flexible, scalable, and accurate network emulators. The desired network emulator should be able to facilitate the emulation of either wireline or wireless networks. In the case when network topology is critical to the underlying network protocol, the emulator should provide specific mechanisms to emulate network topology. In this paper, we present a distributed network emulation system EMPOWER, which not only can fulfill those requirements, but also can generate user-defined network conditions and traffic dynamics at packet level. EMPOWER is highly scalable in that each emulator node could be configured to emulate multiple network nodes. Some significant research issues such as topology mapping scheme and scalability of the emulator are discussed and addressed. Preliminary emulation results show that EMPOWER is capable of assisting the study of both wireless and wireline network protocols and applications.

A Cross-Layer Framework for Association Control in Wireless Mesh Networks

Abstract: The user association mechanism specified by the IEEE 802.11 standard does not consider the channel conditions and the AP load in the association process. Employing the mechanism in its plain form in wireless mesh networks we may only achieve low throughput and low user transmission rates. In this paper we design a new association framework in order to provide optimal association and network performance. In this framework we propose a new channel-quality based user association mechanism inspired by the operation of the infrastructure-based WLANs. Besides, we enforce our framework by proposing an airtime-metric based association mechanism that is aware of the uplink and downlink channel conditions as well as the communication load. We then extend the functionality of this mechanism in a cross-layer manner taking into account information from the routing layer, in order to fit it in the operation of wireless mesh networks. Lastly, we design a hybrid association scheme that can be efficiently applied in real deployments to improve the network performance. We evaluate the performance of our system through simulations and we show that wireless mesh networks that use the proposed association mechanisms are more capable in meeting the needs of QoS-sensitive applications.

Grouping mesh clusters

Abstract: Systems and methods for grouping mesh networks. Mesh networks enable energy data to be transferred from an energy sensing device to a destination device using various networks and reduces the need to install metering stations. Embodiments of the invention join or group mesh networks that otherwise are not able to communicate. The connections between the grouped mesh networks can be passive using directional antennas or passive antennas or active using higher power RF devices, solar repeaters, mobile mesh devices, etc. The energy data is routed in a smart manner, by performing load balancing at gateways, by monitoring the signal to noise ratio of available communication paths, etc. Mesh clusters can also be created to define low power clusters, address blocking clusters, and frequency based clusters. Grouping clusters facilitates the efficient transfer of energy data from an energy sensing device to a energy management station.

Communications protocol for packet data particularly in mesh topology wireless networks

Abstract: In a wireless mesh topology data communications network, a communications method having a type of handshaking protocol for data exchange. A portion of the protocol is synchronous, using a schedule of control channel sessions held at all mutually communicating nodes of the network and a portion of the protocol is asynchronous, relying upon gaps between control channel sessions for transmission of requested data. Nodes which are in line of sight relation request data from each other using a request to send message and a clear to send message. A requesting node sends an RTS message to a neighbor node with information about gaps specifying the location of requested data. A supplying node transmits a potential schedule for sending requested information and the requesting node sends a CTS message agreeing upon the schedule. The potential schedule includes a number of available gaps between known control channel sessions. Because transmissions are scheduled, rapidly switchable directional antennas at requesting and supplying nodes may be used with good advantage.

Low-Latency Broadcast in Multirate Wireless Mesh Networks

Abstract: In a multirate wireless network, a node can dynamically adjust its link transmission rate by switching between different modulation schemes. In the current IEEE802.11a/b/g standards, this rate adjustment is defined for unicast traffic only. In this paper, we consider a wireless mesh network (WMN), where a node can dynamically adjust its link-layer multicast rates to its neighbors, and address the problem of realizing low-latency network-wide broadcast in such a mesh. We first show that the multirate broadcast problem is significantly different from the single-rate case. We will then present an algorithm for achieving low-latency broadcast in a multirate mesh which exploits both the wireless multicast advantage and the multirate nature of the network. Simulations based on current IEEE802.11 parameters show that multirate multicast can reduce broadcast latency by 3-5 times compared with using the lowest rate alone. In addition, we show the significance of the product of transmission rate and transmission coverage area in designing multirate WMNs for broadcast