is prohibited.
that is, the time that the channel is not occupied between two successive bursts. Schedulers
use the information associated with the BCPs, for example, offset time (burst arrival time),
and burst length (burst exit time). In certain Scheduling algorithms, the schedulers need to
keep track of the voids between scheduled burst. Three main channel scheduling algorithms
can be found in the literature: (1) First Fit Unscheduled Channel (FFUC) algorithm, (2)
Latest Available Unscheduled Channel (LAUC) algorithm, and (3) Latest Available Void
Filling (LAVF) algorithm. The implementation and the working of these algorithms are
beyond the scope of this chapter.
Node.Architecture.and.Switching.Technology.
The switching technology is a very critical architectural aspect in the design of OBS networks.
In order to effectively operate an OBS network with efficient bandwidth utilization,
the switching time should be negligible compared to the mean transmission time of the data
bursts. Therefore, both the deployed switching technology and the mean burst length have
to be chosen appropriately. For example, an OBS network using fiber links at the rate of 10
Gbps to transmit a burst of about 1 Mbyte cannot adopt Micro Electro-Mechanical Systems
(MEMS) (Suzuki, Otani, & Hayashi, 2003), since they require switching times between 1-
10 ms, which is greater than the transmission time of an entire burst.
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