Michiaki Hayashi

G-lambda: coordination of a grid scheduler and lambda path service over GMPLS

A vertical coordination between computing resource scheduler and network resource scheduler for Grid-based applications is described. The network resource management system virtualizes and schedules network resources to inter-work with Grid resource scheduler through Web-services interface.

OTDM transmitter using WDM-TDM conversion with an electroabsorption wavelength converter

An all-optical multiplexing technique using wavelength division multiplexing (WDM)-time division multiplexing (TDM) conversion with an electroabsorption wavelength converter has been proposed and demonstrated. The effectiveness of this WDM-TDM conversion technique for various pulsewidth settings was experimentally investigated. The fluctuation of the signal performance, which was inevitably caused by the coherent crosstalk between adjacent pulses in the conventional optical time division multiplexing (OTDM) technique, were successfully suppressed, even in the case of wide pulse duration. High Q-factor performance has been maintained for a wide range of duty ration from 36% to 74%. By introducing this technique to the optical time division multiplexer, a highly stable and high-quality 40-Gb/s optical signal can be effectively produced without generating the short pulse or setting two tributaries at orthogonal polarization states, and without introducing high-speed electronics for signal multiplexing. The WDM-TDM conversion with an electroabsorption wavelength converter was extended to 60-Gb/s operation by using three 20-Gb/s tributaries. A clear eye opening was confirmed for a waveform after the WDM-TDM conversion of the 60-Gb/s signal.

Managing and controlling GMPLS network resources for grid applications

Inter-working between GMPLS network and grid computing application through Web-services interface is demonstrated for the first time. Lambda LSP-based network resource virtualization and scheduling techniques successfully achieves nation-wide grid computing environment with advance reservation operation.

G-lambda: Coordination of a Grid Scheduler and Lambda Path Service over GMPLS

A vertical coordination between computing resource scheduler and network resource scheduler for Grid-based applications is described. The network resource management system virtualizes and schedules network resources to inter-work with Grid resource scheduler through Web-services interface.

Highly reliable optical bidirectional path switched ring networks applicable to photonic IP networks

The reliability of the optical bidirectional path switched ring (OBPSR) network is studied by using optical networking equipment (ONE) with microelectromechanical system (MEMS)-based optical switching fabrics. The reliability of the wavelength path in OBPSR networks is shown to be highly dependent on redundant schemes of switching fabrics in the ONE. This study proposes a new redundant scheme utilizing optical couplers together with controlled switch fabrics without using active selectors, and shows that reliability of the wavelength path can be remarkably improved. A fast redundant switching operation of 10 ms was experimentally confirmed with a prototype of the ONE based on the proposed redundant switching fabrics. Furthermore, interworking operations in terms of the protection and restoration between the optical layer and the Internet protocol (IP) layer are experimentally investigated. In a 500-km optical ring network, fast wavelength path protection switching was confirmed without reconfiguring the link state database of the IP layer, and the measured protection time in the IP layer was as short as 21 ms.

Trends of optical networking technologies

Optical layer networking, such as wavelength routing, switching and restoration/protection in an optical layer is a major trend of future optical networks to achieve highly scaleable and survivable optical backbone networks. In this paper, optical layer networking using MEMS-based optical switches both for ring and mesh networks is discussed. Fast protection time of about 20 ms for IP layer has been achieved by the optical layer protection with the optical network protection equipment using a 2D-MEMS in a 500 km bidirectional wavelength path switching ring network. The obtained switching time was comparable to that of optical cross connect using electrical switching fabrics. Regarding the intelligent optical network using the generalized multi-protocol label switching (GMPLS) protocols, interworking between a photonic cross connect based on a 3D-MEMS and an IP/MPLS router has been confirmed. Fast wavelength path provisioning as well as proper path restoration has been also achieved with the GMPLS testbed including three photonic cross connect nodes and 1000 km bidirectional transmission line. Finally, the feasibility of the transparent all-optical network has been demonstrated with the GMPLS testbed.

Analysis on jitter tolerance of optical 3R regenerator

The dynamic jitter tolerance of the 40-Gb/s optical 3R regenerator was analyzed for a wide range frequency up to 80 MHz according to the ITU-T specification, for the first time. The tolerance was investigated using the cross absorption modulation (XAM) effect of electroabsorption modulators. The tradeoff relation between the jitter suppression effect and the jitter tolerance was experimentally confirmed.

Field trial of 63 channels 40 Gbit/s dispersion-managed soliton WDM signal transmission over 320 km NZ-DSFs

Field trial of 63 channels 40 Gbit/s dispersion-managed soliton WDM signal transmission was successfully demonstrated over 320 km (4 /spl times/ 80 km) installed NZ-DSFs. The obtained Q factor on average was 15.4 dB, and very stable long-term performance was confirmed without PMD compensation.

60 Gbit/s WDM-OTDM transmultiplexing using an electro-absorption modulator

We propose a WDM-OTDM transmultiplexing technique to generate a stable high speed OTDM signal with adjustable pulse width by using an electro-absorption modulator and demonstrate 60 Gbit/s signal generation from three 20 Gbit/s WDM signals.

Advance reservation-based network resource manager with adaptive path discovery scheme for SOA-based networking

Latency-aware adaptive path discovery scheme with optimized resource scheduling mechanism were proposed for the advance reservation-capable SOA-based networking architecture. Using proposed techniques, advance reservation and service modification operations invoked from Web-services interface were experimentally demonstrated.