Katsuhiro Shimano

Demonstration of the highly reliable Hikari router network based on a newly developed disjoint path selection scheme

Integration of multiprotocol label switching functions and multiprotocol lambda switching functions can enhance the throughput of IP networks and remove bottlenecks that are derived from electrical packet processing. To enhance the packet forwarding capability, NTT proposed a photonic MPLS concept that includes MP/spl lambda/S, and demonstrated IP, MPLS, and photonic MPLS integrated router systems called the photonic MPLS router. This router system is now called the Hikari router. The word Hikari is Japanese meaning beam, light, lightwave, optical, photonic, and sunshine. The amount of IP data traffic has grown remarkably. Massive IP routers and flexible route control mechanisms are now required to cope with the increased amount of traffic. The Hikari router can offer two solutions utilizing photonic switching technologies, and photonic network operation and management technologies. The first solution is utilizing photonic switching technologies realized using optical-switch-based crossconnect systems. The other solution is realized using the MPLS and MP/spl lambda/S signaling protocol and photonic network protection functions. In this article we report on the implementation of the Hikari router systems, propose a newly developed disjoint path selection scheme for generalized MPLS networks with shared risk link group constraints, and demonstrate the signaling protocol and network protection functions. The demonstration system achieves a distributed optical path set-up/tear-down protocol with an extended constraint-based routing label distribution protocol. Fast self-healing through automatic protection switching and a new restoration scheme are also implemented. These functions are successfully implemented, and the performance is verified on a demonstration network. The protection switching scheme achieves protection in less than 20 ms, and the optical path restoration scheme achieves restoration in less than 500 ms.

The IP/MPLS over ASON/GMPLS test bed of the IST project LION

A test-bed of a multi-vendor IP/MPLS over ASON/GMPLS network has been realized integrating IP Gigabit routers and optical equipment in a managed multi-domain environment to investigate the realization of soft-permanent optical connections and multi-layer resilience strategies

Demonstration of optical burst data switching using photonic MPLS routers operated by GMPLS signaling

We demonstrate, for the first time, optical burst data switching using photonic MPLS routers controlled by GMPLS. Optical burst data can be transmitted at a bit rate of 10 Gb/s without burst data loss, and high network throughput is achieved.

Photonic MPLS router to create bandwidth-abundant IP networks

This paper describes the concept of the photonic multiprotocol label switching (MPLS) network and prototypes of the photonic MPLS router (PhRter). The photonic MPLS scheme, an expansion of the MPLS scheme, uses photonic labels. The PhRter prototypes utilize wavelength as photonic labels. Optical label switched paths (OLSPs) are formed between ingress to egress PhRters. An OLSP bundles label switched paths (LSPs) belonging to the same forward equivalence classes, and offers cut-through in the optical domain. This cut-through by OLSPs can reduce the electrical forwarding fabric at the intermediate nodes. As a result, node throughput can be vastly expanded. This paper also describes the advances of the planar lightwave circuit optical switch, the key to realize the PhRter. Distributed autonomous control is realized through an OLSP setup/teardown protocol that uses an extended multiprotocol lambda switching (MP/spl lambda/S) signaling technique. The mechanisms of OLSP recovery from network failure, which require the cooperation of IP and photonic networks, are also implemented and their performances demonstrated.

An EDFA gain control and power monitoring scheme for fault detection in WDM networks by employing a power-stabilized control channel

Schemes are proposed for the highly reliable gain control of erbium-doped fiber amplifiers (EDFAs) and for power monitoring to detect faults in wavelength-division-multiplexing (WDM) networks. These schemes employ one WDM channel (a control channel). The EDFA gain and output power levels are controlled by monitoring the control channel power that is automatically controlled and stabilized in the node. This prevents the uncontrolled EDFA operation that might result from any serious change in the control channel power. The use of a power stabilized control channel for power monitoring makes it possible to detect transmission system faults correctly because the monitoring of the control channel power is unaffected by the amplified spontaneous emission (ASE) generated in the EDFA. We also report experimental results on the dependence of the transient response of the EDFA gain and output power on the signal channel power and channel number input into the EDFA, when the power of the control channel changes due to problems with its light source. Numerical calculation of the gain transience explains the experimental results.