Wenzhe Li

A large-scale nesting ring multi-chip architecture for manycore processor systems

Abstract The optical network on chip (ONoC) paradigm has emerged as a promising solution to multi-core/many-core processor systems for offering enormous bandwidth and low power consumption. As chip multiprocessors (CMPs) scale to unprecedented numbers of cores, the performance of next-generation CMPs will be bounded by the process yield and power density of single chip. In earlier work we proposed a multi-chip ONoC architecture that scales to large numbers of CMPs and delivers high performance in terms of delay and throughout. Building on that work, in this paper we propose an optimized architecture for integrating a large number of cores into chips with a novel control strategy, including a contention resolution scheme and a resource reservation scheme. The proposed control strategy is crucial to large scale ONoCs, because the resource reservation scheme ensures efficient wavelength allocation for the traffic while the contention management scheme is effective in reducing the impact of contentions. To sustain good performance and energy efficiency of large-scale ONoC, the topology is optimized to reduce the average transmission distance with minimum increase of power consumption. We evaluate the proposed architecture within a 1000-core processor system and compare it with CMesh and several previously proposed topologies with different control strategies. The simulation results show that, our new large-scale architecture can achieve better performance on throughput and delay.

Nesting ring architecture of multichip optical network on chip for many-core processor systems

Abstract. Optical network on chip (ONoC) is an attractive solution for multicore/many-core processor systems due to its high power efficiency and enormous bandwidth. However, as increasing numbers of cores need to be interconnected, the scalability of a many-core processor on a single chip is limited by its process yield and power density. A multichip architecture is, therefore, proposed to improve the scalability of ONoC. In multichip architectures, the throughput and traffic delay rely on both the intrachip and interchip networks. To exploit the advantages of multichip systems, first we propose a multichip ONoC architecture for a many-core processor system that employs a nesting ring topology. The design principles of multichip systems of different sizes are then investigated to achieve higher throughput and lower delay. These principles include the number of chips and the number of cores per chip, which are considered jointly for the first time. Finally, we evaluate the performance of the proposed architecture, implemented in 240-core and 400-core systems, respectively, and compare it to two other traditional ONoC architectures with respect to throughput and end-to-end (ETE) delay. The results show that the proposed multichip system exhibits good scalability, achieves high throughput, and provides low ETE delay.

Survivable virtual optical network mapping in elastic optical networks with shared backup path protection

In this paper, we study the problem of survivable virtual optical network (VON) mapping against single link failure with shared backup path protection (SBPP) in elastic optical networks. We formulate this problem with an integer linear programming (ILP) model to minimize the resource consumption of both working and backup paths. A different dynamic cost model (DDCM) for each sharable frequency slot (FS) is proposed with the consideration of the flexibility and integrity of VON request. We also propose a shared protection VON mapping (SPVM) algorithm based on DDCM, together with a baseline algorithm for comparison. Numerical results show that the proposed algorithm achieves near optimal results comparing with ILP solution in small-scale network, and also outperforms baseline scheme in terms of blocking probability, resource utilization and backup resource reservation in large-scale network.

Experimental demonstration of software-defined optical network for heterogeneous packet and optical networks

The rapid growth of the network traffic and the diversity of the network requirements bring network service providers new demands and challenges. In order to achieve better efficiency and resource utilization, we need to solve the problems caused by the heterogeneous network environment, such as the low resource utilization and the control and management collaboration problem of heterogeneous networks. The promotion of the software-defined network concept brings the network operators a new way of thinking to solve the problem caused by heterogeneous network environment, especially the convergence of packet and optical network. We propose a control architecture for packet and optical network convergence, including how to be compatible with the existing optical network control architecture. A series of network performance parameters have been demonstrated under various network environments on our testbed.

A Novel K-path based Resource Allocation Scheme for Optical Network on Chip

We employ a

Towards Software-Defined Optical Network: From the perspective of heterogeneous optical networks

K

Spectrum-efficient multipath provisioning with content connectivity for the survivability of elastic optical datacenter networks

-path based resource allocation scheme on optical network-on-chip to avoid contentions. Simulation results show that the performances on ETE delay and throughput are improved with the proposal.

Survivable multipath provisioning with content connectivity in elastic optical datacenter networks

A centralized and unified control mechanism is proposed to merge heterogeneous optical networks into Software-Defined Optical Network (SDON) for dynamic and efficient service delivery. The proposals are experimental demonstrated via a completely extended controller based on Opendaylight (ODL) Project.