Modular expansion and reconfiguration of shufflenets in multi-star implementations.

by Philip Pak-tung To.Thesis (M.Phil.)--Chinese University of Hong Kong, 1994.Includes bibliographical references (leaves 57-60).Chapter 1 --- Introduction --- p.1Chapter 2 --- Modular Expansion of ShuffleNet --- p.8Chapter 2.1 --- Multi-Star Implementation of ShuffleNet --- p.10Chapter 2.2 --- Modular Expansion of ShuffleNet --- p.21Chapter 2.2.1 --- Expansion Phase 1 --- p.21Chapter 2.2.2 --- Subsequent Expansion Phases --- p.24Chapter 2.3 --- Discussions --- p.26Chapter 3 --- Reconfigurability of ShuffleNet in Multi-Star Implementation --- p.33Chapter 3.1 --- Reconfigurability of ShuffleNet --- p.34Chapter 3.1.1 --- Definitions --- p.34Chapter 3.1.2 --- Rearrangable Conditions --- p.35Chapter 3.1.3 --- Formal Representation --- p.38Chapter 3.2 --- Maximizing Network Reconfigurability --- p.40Chapter 3.2.1 --- Rules to maximize Tsc and Rsc --- p.41Chapter 3.2.2 --- Rules to Maximize Z --- p.42Chapter 3.3 --- Channels Assignment Algorithms --- p.43Chapter 3.3.1 --- Channels Assignment Algorithm for w = p --- p.45Chapter 3.3.2 --- Channels Assignment Algorithm for w = p. k --- p.46Chapter 3.3.3 --- Channels Assignment Algorithm for w=Mpk --- p.49Chapter 3.4 --- Discussions --- p.51Chapter 4 --- Conclusions --- p.5

OTIS-Based Multi-Hop Multi-OPS Lightwave Networks

International audienceAdvances in optical technology, such as low loss Optical Passive Star couplers (OPS) and the possibility of building tunable optical transmitters and receivers have increased the interest for multiprocessor architectures based on lightwave networks because of the vast bandwidth available. Many research have been done at both technological and theoretical level. An essential effort has to be done in linking those results. In this paper we propose optical designs for two multi-OPS networks: the single-hop POPS network and the multi-hop stack-Kautz network; using the Optical Transpose Interconnecting System (OTIS) architecture, from the Optoelectronic Computing Group of UCSD. In order to achieve our result, we also provide the optical design of a generalization of the Kautz digraph, using OTIS

Dynamic Optical Networks for Data Centres and Media Production

This thesis explores all-optical networks for data centres, with a particular focus on network designs for live media production. A design for an all-optical data centre network is presented, with experimental verification of the feasibility of the network data plane. The design uses fast tunable (< 200 ns) lasers and coherent receivers across a passive optical star coupler core, forming a network capable of reaching over 1000 nodes. Experimental transmission of 25 Gb/s data across the network core, with combined wavelength switching and time division multiplexing (WS-TDM), is demonstrated. Enhancements to laser tuning time via current pre-emphasis are discussed, including experimental demonstration of fast wavelength switching (< 35 ns) of a single laser between all combinations of 96 wavelengths spaced at 50 GHz over a range wider than the optical C-band. Methods of increasing the overall network throughput by using a higher complexity modulation format are also described, along with designs for line codes to enable pulse amplitude modulation across the WS-TDM network core. The construction of an optical star coupler network core is investigated, by evaluating methods of constructing large star couplers from smaller optical coupler components. By using optical circuit switches to rearrange star coupler connectivity, the network can be partitioned, creating independent reserves of bandwidth and resulting in increased overall network throughput. Several topologies for constructing a star from optical couplers are compared, and algorithms for optimum construction methods are presented. All of the designs target strict criteria for the flexible and dynamic creation of multicast groups, which will enable future live media production workflows in data centres. The data throughput performance of the network designs is simulated under synthetic and practical media production traffic scenarios, showing improved throughput when reconfigurable star couplers are used compared to a single large star. An energy consumption evaluation shows reduced network power consumption compared to incumbent and other proposed data centre network technologies

A Hybrid Beam Steering Free-Space and Fiber Based Optical Data Center Network

Wireless data center networks (DCNs) are promising solutions to mitigate the cabling complexity in traditional wired DCNs and potentially reduce the end-to-end latency with faster propagation speed in free space. Yet, physical architectures in wireless DCNs must be carefully designed regarding wireless link blockage, obstacle bypassing, path loss, interference and spatial efficiency in a dense deployment. This paper presents the physical layer design of a hybrid FSO/in-fiber DCN while guaranteeing an all-optical, single hop, non-oversubscribed and full-bisection bandwidth network. We propose two layouts and analyze their scalability: (1) A static network utilizing only tunable sources which can scale up to 43 racks, 15,609 nodes and 15,609 channels; and (2) a re-configurable network with both tunable sources and piezoelectric actuator (PZT) based beam-steering which can scale up to 8 racks, 2,904 nodes and 185,856 channels at millisecond PZT switching time. Based on a traffic generation framework and a dynamic wavelength-timeslot scheduling algorithm, the system-level network performance is simulated for a 363-node subnet, reaching >99% throughput and 1.23 μ s average scheduler latency at 90% load

Overcoming the Switching Bottlenecks in Wavelength-Routing, Multicast-Enabled Architectures

Modular optical switch architectures combining wavelength routing based on arrayed waveguide grating (AWG) devices and multicasting based on star couplers hold promise for flexibly addressing the exponentially growing traffic demands in a cost- and power-efficient fashion. In a default switching scenario, an input port of the AWG is connected to an output port via a single wavelength. This can severely limit the capacity between broadcast domains, resulting in interdomain traffic switching bottlenecks. An unexplored solution to this issue is to exploit multiple AWG free spectral ranges (FSRs), i.e., to set up multiple parallel connections between each pair of broadcast domains. In this paper, we study, for the first time, the influence of the FSR count on the throughput of a multistage switching architecture and propose a generic and novel analytical framework to estimate the blocking probability. We assess the accuracy of our analytical results via Monte Carlo simulations. Our study points to significant improvements with a moderate increase in the number of FSRs. We show that an FSR count beyond four results in diminishing returns. Furthermore, to investigate the tradeoffs between the network- and physical-layer effects, we conduct a cross-layer analysis, taking into account pulse amplitude modulation and rate-adaptive forward error correction. We illustrate how the effective bit rate per port increases with an increase in the number of FSRs

Some studies on the multi-mesh architecture.

In this thesis, we have reported our investigations on interconnection network architectures based on the idea of a recently proposed multi-processor architecture, Multi-Mesh network. This includes the development of a new interconnection architecture, study of its topological properties and a proposal for implementing Multi-Mesh using optical technology. We have presented a new network topology, called the 3D Multi-Mesh (3D MM) that is an extension of the Multi-Mesh architecture [DDS99]. This network consists of n3 three-dimensional meshes (termed as 3D blocks), each having n3 processors, interconnected in a suitable manner so that the resulting topology is 6-regular with n6 processors and a diameter of only 3n. We have shown that the connectivity of this network is 6. We have explored an algorithm for point-to-point communication on the 3D MM. It is expected that this architecture will enable more efficient algorithm mapping compared to existing architectures. We have also proposed some implementation of the multi-mesh avoiding the electronic bottleneck due to long copper wires for communication between some processors. Our implementation considers a number of realistic scenarios based on hybrid (optical and electronic) communication. One unique feature of this investigation is our use of WDM wavelength routing and the protection scheme. We are not aware of any implementation of interconnection networks using these techniques.Dept. of Computer Science. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .A32. Source: Masters Abstracts International, Volume: 43-03, page: 0868. Adviser: Subir Bandyopadhyay. Thesis (M.Sc.)--University of Windsor (Canada), 2004

A study of topologies and protocols for fiber optic local area network

The emergence of new applications requiring high data traffic necessitates the development of high speed local area networks. Optical fiber is selected as the transmission medium due to its inherent advantages over other possible media and the dual optical bus architecture is shown to be the most suitable topology. Asynchronous access protocols, including token, random, hybrid random/token, and virtual token schemes, are developed and analyzed. Exact expressions for insertion delay and utilization at light and heavy load are derived, and intermediate load behavior is investigated by simulation. A new tokenless adaptive scheme whose control depends only on the detection of activity on the channel is shown to outperform round-robin schemes under uneven loads and multipacket traffic and to perform optimally at light load. An approximate solution to the queueing delay for an oscillating polling scheme under chaining is obtained and results are compared with simulation. Solutions to the problem of building systems with a large number of stations are presented, including maximization of the number of optical couplers, and the use of passive star/bus topologies, bridges and gateways