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1.
All-optical multihop networks, where the data portion of a packet is maintained in an optically encoded format from the source to the destination, can be achieved by augmenting optical switching nodes with optical buffering. Topologically, the ShuffleNet network is a strong contender for implementing such networks ranging from cluster networks to metropolitan area networks. The performance of a regular multihop network whose nodes are augmented with optical buffering and use deflection routing is evaluated. Using the ShuffleNet network as an example, we show that performance, in terms of throughput, average delay, and loss probability, can be improved as multiple fiber delay loops are added for a large range of network parameters. We then compare the performance of ShuffleNet with the Manhattan Street networks with similar features.  相似文献   

2.
GEMNET is a generalization of shuffle-exchange networks and it can represent a family of network structures (including ShuffleNet and de Bruijn graph) for an arbitrary number of nodes. GEMNET employs a regular interconnection graph with highly desirable properties such as small nodal degree, simple routing, small diameter, and growth capability (viz. scalability). GEMNET can serve as a logical (virtual), packet-switched, multihop topology which can be employed for constructing the next generation of lightwave networks using wavelength-division multiplexing (WDM). Various properties of GEMNET are studied  相似文献   

3.
简单介绍了广义洗牌网络(GSN)的结构和分类,着重分析缩减级型GSN的平均跳距性能,并提出一种计算平均跳距的算法  相似文献   

4.
A multihop, wavelength division multiplex (WDM) based network, BanyanNet, is proposed for the realization of terabit lightwave networks, BanyanNet can he considered as a the bidirectional equivalent of the popular ShuffleNet. Exploiting its representation, we developed a fast, decentralized, bidirectional routing algorithm for BanyanNet. The performance of BanyanNet is compared to that of the ShuffleNet and bilayered ShuffleNet. For N=pm×k networks, the p=2 BanyanNet provides better performance in channel efficiency, total and user throughput than the corresponding ShuffleNet, and offers more flexible network configurations than the bilayered and p=4 ShuffleNet  相似文献   

5.
文章介绍了多跳网(ShuffleNet)的结构和路由算法,提出了一种新型的ShuffleNet等效时分复用网络,给出了该网络结构的路由算法,并对8节点的基于光时分复用的ShuffleNet等效网络性能进行了分析。  相似文献   

6.
A new generation of integrated services local networks (ISLN's) is needed to yield to local area users the provision of voice, data, and images in a cost-effective manner. Besides high-speed and service integration features, these advanced multiservice communication systems have to also provide powerful interconnection with both public networks and traditional LAN's. So conception and design of the interconnection units, i.e., gateways and bridges, have to be carried out contextually with the network architecture definition. The paper addresses the interworking solutions adopted for a local integrated optical network (LION) currently under development. The architecture of bridges and gateways allowing users belonging to different LION subnetworks to communicate with public networks and commercial systems is also described. In particular, the interconnection with the integrated services digital network (ISDN) is highlighted.  相似文献   

7.
A modified multihop ShuffleNet configuration for WDM all-optical networks is described which is rearrangeable and allows wavelength reuse at each node as it expands. This configuration does not require any rearrangement of preceding node and wavelength assignments when new nodes and wavelengths are added and it can function with fewer overall number of nodes. By comparison, the traditional Perfect ShuffleNet requires a large number of nodes to be available for any updating of the configuration. Most of these nodes remain idle during the normal signal routing process leading to reduced network link capacity. Furthermore, to facilitate wavelength reuse when updating, the Perfect ShuffleNet necessitates the rearrangement of preceding node and wavelength assignments. This leads to generalized forms of ShuffleNet where wavelength reuse forces network architecture into irregular topologies. The modified ShuffleNet proposed here is capable of facilitating wavelength reuse without the modification of initial node and wavelength assignments and could be realised by using a star topology.  相似文献   

8.
ShuffleNet is one of the many architectures proposed for multihop lightwave networks. Its advantages include low mean-internodal distance and simple routing. Modular growth of ShuffleNets, however, is generally difficult and requires many hardware and software reconfigurations. The authors consider a multistar implementation of ShuffleNet and discuss how a (p,k) ShuffleNet can be expanded to a (p,k+1) ShuffleNet in modular phases, where each phase increases the number of nodes by only a small fraction and requires only minor hardware and software reconfigurations  相似文献   

9.
Cellular networks have been widely used to support many new audio-and video-based multimedia applications. The demand for higher data rate and diverse services has driven the research on multihop cellular networks (MCNs). With its ad hoc network features, an MCN can offer many additional advantages, such as increased network throughput, scalability and coverage. However, providing ad hoc capability to MCNs is challenging as it may require proper wireless interfaces. In this article, the architecture of IEEE 802.16 network interface to provide ad hoc capability for MCNs is investigated, with its focus on the IEEE 802.16 mesh networking and scheduling. Several distributed routing algorithms based on network entry mechanism are studied and compared with a centralized routing algorithm. It is observed from the simulation results that 802.16 mesh networks have limitations on providing sufficient bandwidth for the traffic from the cellular base stations when a cellular network size is relatively large.  相似文献   

10.
Substantial attention has recently been given to the implementation of sort-banyan networks for switching asynchronous transfer mode (ATM) transmission links in a BISDN (broadband integrated service digital network) network. The author gives a three-dimensional view of the theory and implementation of switching, as well as variations of the basic scheme. ATM switches are classified as blocking versus nonblocking, unicast versus multicast, and input queued versus output queued. Sorting networks structured by a three-dimensional interconnection topology are studied. A sorting network, when coupled with a banyan routing network structured in three dimensions, becomes a self-routing and nonblocking switching network. This three-dimensional topology allows CMOS VLSI implementations of the subnetworks and interconnection of these subnetworks at a speed of 150 Mb/s and beyond. The sorting mechanism can also be used for output conflict resolution, subsequently making the switch suitable for ATM switching. Recent enhancements, which provide features such as parallelism, trunk grouping, and modularity, are also described. These features enhance the throughput/delay performance, provide better fault and synchronization tolerance, and enable more economical growth for switch size  相似文献   

11.
The IEEE 802.11 MAC protocol is the standard for wireless LANs; it is widely used in testbeds and simulations for wireless multihop ad hoc networks. However, this protocol was not designed for multihop networks. Although it can support some ad hoc network architecture, it is not intended to support the wireless mobile ad hoc network, in which multihop connectivity is one of the most prominent features. In this article we focus on the following question: can the IEEE 802.11 MAC protocol function well in multihop networks? By presenting several serious problems encountered in an IEEE 802.11-based multihop network and revealing the in-depth cause of these problems, we conclude that the current version of this wireless LAN protocol does not function well in multihop ad hoc networks. We thus doubt whether the WaveLAN-based system is workable as a mobile ad hoc testbed  相似文献   

12.
A critical component of any large-scale parallel processing system is the interconnection network that provides a means for communication along the system's processors and memories. Attributes of the multistage cube topology that have made it an effective basis for interconnection networks and the subject of much ongoing research are reviewed. These attributes include O(N log2N) cost for an N-input/output network, decentralized control, a variety of implementation options, good data-permuting capability to support single-instruction-stream/multiple-data-stream (SIMD) parallelism, good throughput to support multiple-instruction-stream/multiple-data-stream (MIMD) parallelism, and ability to be partitioned into independent subnetworks to support reconfigurable systems. Examples of existing systems that use multistage cube networks are considered. The multistage cube topology can be converted into a single-stage network by associating with each switch in the network a processor (and a memory). Properties of systems that use the multistage cube network in this way are examined  相似文献   

13.
We propose a multihop network called TIONet or triangular interconnection of optical networks. The graph is examined from routing and scaling approaches. A store and forward routing scheme is assumed  相似文献   

14.
The concept of a forwarding node, which receives packets from upstream nodes and then transmits these packets to downstream nodes, is a key element of any multihop network, wired or wireless. While high-speed IP router architectures have been extensively studied for wired networks, the concept of a "wireless IP router" has not been addressed so far. We examine the limitations of the IEEE 802.11 MAC protocol in supporting a low-latency and high-throughput IP datapath comprising multiple wireless LAN hops. We first propose a wireless IP forwarding architecture that uses MPLS with modifications to 802.11 MAC to significantly improve packet forwarding efficiency. We then study further enhancements to 802.11 MAC that improve system throughput by allowing a larger number of concurrent packet transmissions in multihop 802.11-based IP networks. With 802.11 poised to be the dominant technology for wireless LANs, we believe a combined approach to MAC, packet forwarding, and transport layer protocols is needed to make high-performance multihop 802.11 networks practically viable.  相似文献   

15.
We discuss the problem of designing translucent optical networks composed of restorable, transparent subnetworks interconnected via transponders. We develop an integer linear programming (ILP) formulation for partitioning an optical network topology into subnetworks, where the subnetworks are determined subject to the constraints that each subnetwork satisfies size limitations, and it is two-connected. A greedy heuristic partitioning algorithm is proposed for planar network topologies. We use section restoration for translucent networks where failed connections are rerouted within the subnetwork which contains the failed link. The network design problem of determining working and restoration capacities with section restoration is formulated as an ILP problem. Numerical results show that fiber costs with section restoration are close to those with path restoration for mesh topologies used in this study. It is also shown that the number of transponders with the translucent network architecture is substantially reduced compared to opaque networks.  相似文献   

16.
This paper presents the design and experimental results of an optical packet-switching testbed capable of performing message routing with single wavelength time division multiplexed (TDM) packet bit rates as high as 100 Gb/s. The physical topology of the packet-switched optical networking demonstration (POND) node is based on an eight-node ShuffleNet architecture. The key enabling technologies required to implement the node such as ultrafast packet generation, high-speed packet demultiplexing, and efficient packet routing schemes are described in detail. The routing approach taken is a hybrid implementation in which the packet data is maintained purely in the optical domain from source to destination whereas control information is read from the packet header at each node and converted to the electrical domain for an efficient means of implementing routing control. The technologies developed for the interconnection network presented in this paper can be applied to larger metropolitan and wide area networks as well  相似文献   

17.
There has been much interest in using optics to implement computer interconnection networks. However, there has been little discussion of any renting methodologies besides those already used in electronics. In this paper, a neural network routing methodology is proposed that can generate control bits for a broad range of optical multistage interconnection networks (OMIN's). Though we present no optical implementation of this methodology, we illustrate its control for an optical interconnection network. These OMIN's can be used as communication media for distributed computing systems. The routing methodology makes use of an artificial neural network (ANN) that functions as a parallel computer for generating the routes. The neural network routing scheme can be applied to electrical as well as optical interconnection networks. However, since the ANN can be implemented using optics, this routing approach is especially appealing for an optical computing environment. Although the ANN does not always generate the best solution, the parallel nature of the ANN computation may make this routing scheme faster than conventional routing approaches, especially for OMIN's that have an irregular structure. Furthermore, the ANN router is fault-tolerant. Results are shown for generating routes in a 16×16, 3-stage OMIN  相似文献   

18.
The unique systems opportunities offered by, and the unique systems constraints imposed by, lightwave technology as it applies to the field of distributed packet networks are examined. Single-channel and star topology approaches are first considered. Terabit-capacity lightwave networks are discussed, covering both wavelength-division and time-division multiplexing. Multichannel multihop lightwave networks are then considered, and a particular implementation, the ShuffleNet, is described, and its performance, as well as some simple addressing and routing schemes, is discussed  相似文献   

19.
In order to enable fast deployment of new emerging services over multihop wireless networks, it is important to design an efficient service-based platform with the necessary traffic management capabilities. In this paper, we propose a new distributed service-oriented framework for wireless multihop networks, called MultiServ, in which it adopts a quantitative approach toward optimal traffic distribution. Under Multiserv framework, an efficient overlay network can be easily constructed that can greatly facilitate the deployment of new services. We use media streaming and application level multicast as examples to illustrate how the services can be supported. The performance results demonstrate that MultiServ can substantially outperform the conventional approach and achieves comparable performance obtained by a centralized scheme.  相似文献   

20.
Unmanned aerial vehicles (UAVs) have become widespread because of their involvement in a variety of applications. The task of designing the energy-efficient routing between UAVs has been considered a matter of great interest due to the inherent challenges of controlling the dynamics exhibited by UAVs. Energy limitations are considered the main limitations of UAVs. This research paper proposes a novel routing protocol, adaptive ranking and mobile sink (MS)-enabled energy-efficient geographic routing (ARMS-EGR) for flying ad hoc networks. In ARMS-EGR, the whole network is partitioned into cells. The cell contains cell members (CM) and cell heads (CHs). The CH works as a cluster head. Additionally, two MSs have been used to collect data captured by CM. Multihop communication on the network leads to an increase in traffic and consumes the energy of the UAVs located near the base station (BS). MSs are used for power distribution and load balancing across the network. Adaptive ranking of forwarder UAVs and CHs is performed during intracell and intercell multihop communication, respectively, using adaptive ranking. A cell with one-hop communication can directly send packets to the MS, but the ARMS-EGR routing protocol has been proposed for multihop communication. The proposed approach is simulated in NS-2.35 software. The results show that end-to-end latency and power consumption during packet transmission are greatly minimized. ARMS-EGR also demonstrates improvements in message success rates, number of alive nodes, and packet delivery ratio, making ARMS-EGR particularly suitable for flying ad hoc networks (FANETs).  相似文献   

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