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Yongmin QI Wei GUO Yi ZHANG Siye ZUO Yaohui JIN Weisheng HU
We study the configuration issue of three-stage multi-granularity optical cross-connects (MG-OXC) for the dynamic traffic model in all-optical networks. From the single node point of view, we propose a configuration algorithm to configure different granularity cross-connects for arrival sub-requests with different traffic types and bandwidths. The performance of the configuration algorithm is evaluated by simulation and, furthermore, is validated by experiment based on our flexible Multi-functional Optical Switching Testbed (MOST).
Yoshiaki YAMABAYASHI Masafumi KOGA Satoru OKAMOTO
In order that they fully support human activities, new network services and applications are overwhelming conventional ones, such as telephony, facsimile, and telegraph. Demands for digital networks are exploding, not only in terms of quantity but also quality. Nobody can predict where these demands will lead. Traffic engineering, which is impossible in pure Internet protocol (IP) -based networks, is recognized as being indispensable for quality of service (QoS) control. It includes guaranteed services in terms of bandwidth, delay, delay variation (jitter), and service protection. The "engineered tunnel" through IP network supports virtual private networks (VPNs) and allows us to develop voice-over-IP (VoIP), teleconferencing and other secure private network services. This paper proposes the "photonic router" which makes use of wavelength-based networks for signal routing. IP packets having the same destination are bundled into a wavelength path. Interchange nodes along the path route control path routing on the basis of wavelength information, not on IP headers, which can not be read or processed with current optical techniques. In short, wavelength path routing offers "cut-through" in the photonic layer. This paper shows its feasibility by describing the combination of an optical cross-connect, payload assembler/disassembler, label controller, and IP router. Optical cross-connect systems, which are now being intensively studied worldwide, are deemed to be key equipment for a wavelength-path network with centralized control system. This paper proposes to apply the cross-connect to an IP network with distributed autonomous control.