Showing papers on "Wireless mesh network published in 1995"
Patent•
13 Dec 1995
TL;DR: In this paper, a wide area paging broadcast channel for transmitting a page signal throughout a prescribed geographic area over a broadcast channel in response to a page request is considered, where the backhaul to the paging control center is accomplished by a plurality of base stations.
Abstract: A wide area paging broadcast channel for transmitting a page signal throughout a prescribed geographic area over a broadcast channel in response to a page request. At least one subscriber transceiver is located within the prescribe geographic area for receiving the page. In response to the received page signal, the subscriber transceiver transmits information back to the paging control center. However, the backhaul to the paging control center is accomplished by a plurality of base stations. Each base station forms a node in a mesh network of base stations which covers the prescribed geographic area. The subscriber transceiver may transmit information packets to nodes within the mesh network using a multiple access scheme with or without carrier sense access. The mesh network automatically selects which neighboring node to use for forwarding packets. Finally, a gateway device links the mesh network of base stations to the control center. The gateway device then forwards the transmitted information from the subscriber transceiver to the paging control center over the telephone network.
41 citations
Patent•
IBM1
TL;DR: In this paper, the authors propose a method to define a target logical mesh architecture from the hardware architecture, given the possibility that one or more faults are present, by initially defining logical blocks of nodes from among the functional nodes of the HMM architecture.
Abstract: A method is disclosed, for use with a multiprocessing hardware mesh architecture including nodes and a network of interconnections between the nodes, for defining and implementing a target logical mesh architecture utilizing a given subset of the nodes and the interconnections of the hardware architecture. Typically, the hardware mesh architecture includes redundant nodes and interconnections, sot hat the target logical mesh architecture may be defined from the hardware architecture several different ways. As a consequence, the target logical mesh architecture may be defined even in the presence of faulty nodes or interconnections in the hardware architecture. Frequently, the logical mesh is defined in terms of some regular pattern of interconnections. The method of the invention facilitates the definition of the desired logical mesh architecture from the hardware architecture, given the possibility that one or more faults are present, by initially defining logical blocks of nodes from among the functional nodes of the hardware architecture. Then, functional edges between the nodes defined within the logical blocks are defined as logical interconnections between the nodes of the logical blocks, such that the logical blocks, with the interconnections, are structurally consistent with portions of the logical mesh. Finally, additional edges are defined as logical interconnections between nodes in different logical blocks, these additional edges also being consistent with the structure of the logical mesh. The result is that the logical mesh has been fully defined from functional nodes and interconnections in the hardware architecture.
21 citations
06 Apr 1995
TL;DR: The problem of network formation is posed as an adaptive learning problem, in particular, a self-organizing map of locally competitive wireless units that recursively update their positions and individual operating configurations at each iterative step of the neural algorithm.
Abstract: The optimal location of wireless transceivers or communicating sensor devices in an urban area and within large human-made structures is considered. The purpose of the positioning of the devices is formation of a distributed network, either in a mesh or hub-spoke topology, that achieves robust connectivity of the nodes. Real-world examples include wireless local area networks (LANs) within buildings and radio beacons in an outdoor mobile radio environment. Operating environments contain both fixed and moving interferers that correspond to both stationary and time-varying spatial distributions of path distortion of stationary and transient fading and multipath delays that impede connectivity. The positioning of the autonomous wireless devices in an area with an unknown spatial pattern of interferers would normally be a slow incremental process. The proposed objective is determination of the spatial distribution of the devices to achieve the maximum radio connectivity in a minimal number of iterative steps. Impeding the optimal distribution of wireless nodes is the corresponding distribution of environmental interferers in the area or volume of network operation. The problem of network formation is posed as an adaptive learning problem, in particular, a self-organizing map of locally competitive wireless units that recursively update their positions and individual operating configurations at each iterative step of the neural algorithm. The scheme allows the wireless units to adaptively learn the pattern distribution of interferers in their operating environment based on the level of radio interference measured at each node by an equivalent received signal strength from wireless units within the node's hearing distance. Two cases are considered. The first is an indoor human-made environment where the interference pattern is largely deterministic and stationary and the units are positioned to form a wireless LAN. The second situation applies to an outdoor urban environment, where a fixed number of units on mobile platforms operating in a random spatial distribution of interferers.
18 citations
02 Apr 1995
TL;DR: A two level high speed network architecture that combines the throughput advantage of optical networks and the intelligence of electronic processing is presented and a modified dynamic allocation scheme is presented for single-hop packet switching.
Abstract: Optical networks can provide higher throughputs while high speed electronic networks possess the intelligence for network control and management. We present a two level high speed network architecture that combines the throughput advantage of optical networks and the intelligence of electronic processing. One level is a high speed mesh LAN which uses wormhole routing, source routing and hop-by-hop flow control mechanisms with mesh routers (asynchronous pipelined crossbar switches) to provide a high speed electronic network. The second level is an optical star network interconnecting high speed mesh networks distributed across metropolitan area distances. We obtain analytical expressions for the average message (worm) delays for the GTDM (group time division multiplexing) multi-access protocol (which includes as special cases TDM and DAS) for single-hop packet switching in the optical network of such an architecture. We use a two state discrete time Markov chain to model the arrival of messages to the optical network. Results for both uniform traffic and non-uniform traffic are presented. Finally, a modified dynamic allocation scheme is presented for single-hop packet switching which handles the message as a unit rather than sending a message as several fixed sized packets.
5 citations
12 Sep 1995
TL;DR: Though the algorithm was designed with mesh networks in mind, it can be applied to the simpler problem of the constrained minimum spanning tree and the results compare very favourably with those obtained from existing design techniques.
Abstract: This paper presents a genetic algorithm for the design of an optimal mesh network. The problem is of relevance in the design of communication networks where the backbone switching network takes the form of a highly connected mesh in order to provide reliability in the event of switch/link failure. The proposed algorithm addresses two important aspects of the problem-topology design and capacity allocation. The optimisation is done with respect to connection costs subject to performance (delay), connectivity and capacity constraints. Connection costs are assumed to depend on distance and link capacity. Though the algorithm was designed with mesh networks in mind, it can be applied to the simpler problem of the constrained minimum spanning tree. The algorithm has been tested on a tree network and two mesh networks. The results compare very favourably with those obtained from existing design techniques.
5 citations
03 Jul 1995
TL;DR: This paper proposes a fast distributed rerouting algorithm based on a new approach for generation of the restoration paths and the performances of the proposed algorithms are evaluated in terms of restoration efficiency and restoration time.
Abstract: Future telecommunication services will demand a fault-tolerant network with complete survivability. In this context, the reconfiguration of a network in real time has become one of the key issues on network reliability. In continuation of our previous work presented in [3], this paper proposes a fast distributed rerouting algorithm based on a new approach for generation of the restoration paths. The performances of the proposed algorithms are evaluated in terms of restoration efficiency and restoration time.
1 citations
28 Mar 1995
TL;DR: Results show that availability is poor in current networks, but can be significantly improved by combining simple existing techniques, and a minimal or no change in routing hardware complexity.
Abstract: Failure of network hardware components in parallel systems results in deterioration of the communication support provided to various nodes. Limited communication capability may result in the unavailability of one or more nodes to users. In this paper, we develop a framework to study the effect of faulty network components on node availability. We use the framework to investigate the specific case of wormhole routed mesh networks under random faults, and evaluate availability for various routing schemes. Results show that availability is poor in current networks, but can be significantly improved by combining simple existing techniques, and a minimal or no change in routing hardware complexity. >