Hiroaki Harai

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We study routing methods in all–optical switching networks. In all–optical switching networks, the connection with more hops encounters more call blocking, and it is especially true in optical networks with no wavelength conversions. We therefore consider an alternate routing method with limited trunk reservation in which connections with more hops are(More)
We develop a method of high-speed buffer management for output-buffered photonic packet switches. The use of optical fiber delay lines is a promising solution to constructing optical buffers. The buffer manager determines packet delays in the fiber delay line buffer before the packets arrive at the buffer. We propose a buffer management method based on a(More)
Previous analytic approaches for all-optical networks have only allowed a random wavelength assignment policy in spite of the fact that network performance can be improved by other wavelength assignment policies such as first-fit wavelength assignment. In this paper, we develop an approximate analytic method to allow flexible wavelength assignment policies(More)
Previous works have shown that wavelength conversion can considerably improve the performance in all–optical networks. However , it is an unrealistic assumption under the current technology and wavelength conversion with a limited range, not a full range, is more promising. In this paper, we propose a new analytic approach for such networks by virtue of the(More)
SUMMARY The scalability of routing protocol has been considered as a key issue in large–scaled wavelength routed networks. Hierarchical routing scales well by yielding enormous reductions in routing table length, but it also increases path length. This increased path length in wavelength–routed networks leads to increased blocking probability because longer(More)