Figure 5 Sp Scheduling; Figure 6 Wrr Scheduling - Zte ZXR10 5900 Product Description

ZXR10 5900 5200 Product Description
that the interface can send. At the same time, the FIFO sends the packets out of the
queue at the exit at their in-queue sequence on FIFO basis.
2. Strict Priority Queuing, SP
Figure 5 SP Scheduling
As shown in Figure 5, the Strict Priority Queuing (SP hereinafter) classifies the packets,
based on VLAN CoS value, IP packet priority/DSCP, or n-tuple conditions. In the
example shown in Figure 5, all the packets are classified into four types to belong to any
of the four SP queues, and respectively sent to the corresponding queue based on their
types. The four SP queues are high-priority, medium-priority, normal-priority, and low-
priority queues. When the SP sends packets out of the queue, it first sends out packets
from the high-priority queue until all packets in high-priority queue are sent out. Then SP
sends those in the medium-priority queue until no packet is left in the medium-priority
queue. Then it proceeds to sending those in the normal-priority queue and low-priority
queue in turn. In this way packets classified into higher priority are sent first, and those
with lower priority will be postponed by those of higher priority in case of congestion. In
this mechanism, packets (such as VOIP) of higher priority are processed firstly, leaving
those of lower priority (such as E-Mail) processed when the network is idle after critical
services are done, which ensures the priority of higher priority services and makes full
use of network resources as well.
3. Weighted Round Robin Queuing, WRR
Figure 6 WRR scheduling
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