Scalability and power consumption of static optical core networks

Abstract — A large amount of traffic in core networks is highly aggregated and core nodes are interconnected by high-capacity links. Thus, most of the traffic demands in the core area can be accommodated by providing more or less static connections between ingress and egress nodes. In this paper, we describe and study three particular realizations of static optical core networks and compare them with the dynamic, packet switched architecture based on wavelength-division multiplexing (WDM) transmission and conventional electronic packet routers. We introduce an analytical model for estimating the average number of required switch ports for different network topologies in order to assess both scalability and power consumption of the considered network concepts. The results show that the concept of a static optically transparent core network promises high energy efficiency, and scalability to several tens of nodes. I

Scalability and power consumption of static optical core networks

Abstract — A large amount of traffic in core networks is highly aggregated and core nodes are interconnected by high-capacity links. Thus, most of the traffic demands in the core area can be accommodated by providing more or less static connections between ingress and egress nodes. In this paper, we describe and study three particular realizations of static optical core networks and compare them with the dynamic, packet switched architecture based on wavelength-division multiplexing (WDM) transmission and conventional electronic packet routers. We introduce an analytical model for estimating the average number of required switch ports for different network topologies in order to assess both scalability and power consumption of the considered network concepts. The results show that the concept of a static optically transparent core network promises high energy efficiency, and scalability to several tens of nodes. I

Simulating a Pipelined Reconfigurable Mesh on a Linear Array with a Reconfigurable Pipelined Bus System

Due to the unidirectional nature of propagation and predictable delays, optically pipelined buses have been gaining more attention. There have been many models proposed over time that use reconfigurable optically pipelined buses. The reconfigurable nature of the models makes them capable of changing their component’s functionalities and structure that connects the components at every step of computation. There are both one dimensional as well as k –dimensional models that have been proposed in the literature. Though equivalence between various one dimensional models and equivalence between different two dimensional models had been established, so far there has not been any attempt to explore the relationship between a one dimensional model and a two dimensional model. In the proposed research work it is shown that a move from one to two or more dimensions does not cause any increase in the volume of communication between the processors as they communicate in a pipelined manner on the same optical bus. When moving from two dimensions to one dimension, the challenge is to map the processors so that those belonging to a two-dimensional bus segment are contiguous and in the same order on the one-dimensional model. This does not increase any increase in communication overhead as the processors instead of communicating on two dimensional buses now communicate on a linear one dimensional bus structure. To explore the relationship between one dimensional and two dimensional models a commonly used model Linear Array with a Reconfigurable Pipelined Bus System (LARPBS) and its two dimensional counterpart Pipelined Reconfigurable Mesh (PR-Mesh) are chosen Here an attempt has been made to present a simulation of a two dimensional PR-Mesh on a one dimensional LARPBS to establish complexity of the models with respect to one another, and to determine the efficiency with which the LARPBS can simulate the PR-Mesh

Access and metro network convergence for flexible end-to-end network design

This paper reports on the architectural, protocol, physical layer, and integrated testbed demonstrations carried out by the DISCUS FP7 consortium in the area of access - metro network convergence. Our architecture modeling results show the vast potential for cost and power savings that node consolidation can bring. The architecture, however, also recognizes the limits of long-reach transmission for low-latency 5G services and proposes ways to address such shortcomings in future projects. The testbed results, which have been conducted end-to-end, across access - metro and core, and have targeted all the layers of the network from the application down to the physical layer, show the practical feasibility of the concepts proposed in the project

Efficient parallel processing with optical interconnections

With the advances in VLSI technology, it is now possible to build chips which can each contain thousands of processors. The efficiency of such chips in executing parallel algorithms heavily depends on the interconnection topology of the processors. It is not possible to build a fully interconnected network of processors with constant fan-in/fan-out using electrical interconnections. Free space optics is a remedy to this limitation. Qualities exclusive to the optical medium are its ability to be directed for propagation in free space and the property that optical channels can cross in space without any interference. In this thesis, we present an electro-optical interconnected architecture named Optical Reconfigurable Mesh (ORM). It is based on an existing optical model of computation. There are two layers in the architecture. The processing layer is a reconfigurable mesh and the deflecting layer contains optical devices to deflect light beams. ORM provides three types of communication mechanisms. The first is for arbitrary planar connections among sets of locally connected processors using the reconfigurable mesh. The second is for arbitrary connections among N of the processors using the electrical buses on the processing layer and N2 fixed passive deflecting units on the deflection layer. The third is for arbitrary connections among any of the N2 processors using the N2 mechanically reconfigurable deflectors in the deflection layer. The third type of communication mechanisms is significantly slower than the other two. Therefore, it is desirable to avoid reconfiguring this type of communication during the execution of the algorithms. Instead, the optical reconfiguration can be done before the execution of each algorithm begins. Determining a right configuration that would be suitable for the entire configuration of a task execution is studied in this thesis. The basic data movements for each of the mechanisms are studied. Finally, to show the power of ORM, we use all three types of communication mechanisms in the first O(logN) time algorithm for finding the convex hulls of all figures in an N x N binary image presented in this thesis

Optically programmable gate array

The Optically Programmable Gate Array (OPGA), an optical version of a conventional FPGA, benefits from a direct parallel interface between an optical memory and a logic circuit. The OPGA utilizes a holographic memory accessed by an array of VCSELs to program its logic. An active pixel sensor array incorporated into the OPGA chip makes it possible to optically address the logic in a very short time allowing for rapid dynamic reconfiguration. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module can be made compact. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and database search

Reconfigurable Robust Routing for Mobile Outreach Network

The Reconfigurable Robust Routing for Mobile Outreach Network (R3MOO N) provides advanced communications networking technologies suitable for the lunar surface environment and applications. The R3MOON techn ology is based on a detailed concept of operations tailored for luna r surface networks, and includes intelligent routing algorithms and wireless mesh network implementation on AGNC's Coremicro Robots. The product's features include an integrated communication solution inco rporating energy efficiency and disruption-tolerance in a mobile ad h oc network, and a real-time control module to provide researchers an d engineers a convenient tool for reconfiguration, investigation, an d management