is prohibited.
requests, since the ratio between the control information and transmitted data gets smaller.
Furthermore, the efficiency of optical switching is improved due to the reduction in the
mean inter-arrival time between the switched data units (bursts).
Generally, the assembly algorithms are based on a threshold that could be time, burst-length,
or hybrid time-length threshold. In a single data burst, the assembled data units may belong
to various upper layer traffic flows, and ultimately destined to different final destinations;
however, the destination OBS egress node of all the data units must be the same. The arriving
upper layer packets are stored in appropriate queues (according to their egress destination,
QoS requirement, Class of Service (CoS)) in the burst assembler. A new burst is
constructed and its control packet is generated when the threshold is reached. Obviously,
the generated traffic will have variable burst length and constant inter-arrival time, if the
algorithm operates only based on time as threshold; however, this may produce excessively
large data bursts if the upper layer traffic streams are experiencing high loads. Conversely, if
the algorithm operates based on the burst-length threshold, the inter-arrival time will vary,
while the burst length is maintained constant.
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