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Issue No.03 - March (2001 vol.50)
pp: 197-214
ABSTRACT
<p><b>Abstract</b>—In this paper, we devise a preallocation-based single-hop wavelength division multiple access (WDMA) scheme to support temporal quality of service (QoS) in star-coupled optical networks. We consider a star-coupled broadcast-and-select network architecture in which <tmath>$N$</tmath> stations are connected to a star coupler with <tmath>$W$</tmath> different wavelength channels. Each of the <tmath>$W$</tmath> wavelength channels is slotted and shared by the <tmath>$N$</tmath> stations by means of time division multiplexing. Depending on the tunability characteristics (tunable or fixed tuned) of the transmitters/receivers, we classify the network architecture as tunable transmitter/fixed tuned receiver (TT-FR), fixed tuned transmitter/tunable receiver (FT-TR), and tunable transmitter/tunable receiver (TT-TR). We first characterize each real-time message stream <tmath>$M_i$</tmath> with two parameters, the relative message deadline <tmath>$D_i$</tmath> and the maximum (total) message size <tmath>$C_i$</tmath> that can arrive within any time interval of length <tmath>$D_i$</tmath>. We then discuss a restricted case in a TT-FR (or FT-TR) system in which the message streams from a source station are assumed to be all destined for the same destination station. Under this assumption, no source/destination conflicts may occur. We propose a preallocation-based slot assignment scheme to preallocate slots to a set of isochronous message streams, <tmath>$\{M_i=(C_i,D_i) \mid 1 \leq i \leq n\}$</tmath> in such a way that, in any time window of size <tmath>$D_i$</tmath> slots, at least <tmath>$C_i$</tmath> slots on a wavelength channel are allocated to <tmath>$M_i$</tmath> for all <tmath>$i$</tmath>. With the solution derived in the restricted case as a basis, we then consider slot assignment in a (general) TT-TR system and propose a <it>binary splitting</it> scheme to assign each message stream sufficient and well-spaced slots to fulfill its temporal requirement, subject to the source/destination conflict constraints. We rigorously prove the invariance properties, and the correctness, of the binary splitting scheme.</p>
INDEX TERMS
Temporal quality of service, slot assignment, WDMA/TDMA, star-coupled optical networks.
CITATION
Hung-Ying Tyan, Jennifer C. Hou, Bin Wang, Ching-Chih Han, "On Supporting Temporal Quality of Service in WDMA-Based Star-Coupled Optical Networks", IEEE Transactions on Computers, vol.50, no. 3, pp. 197-214, March 2001, doi:10.1109/12.910812