Hol Blocking Pevention - D-Link xStack DES-3528 series User Manual

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xStack DES-3528/DES-3552 Series Layer 2 Stackable Fast Ethernet Managed Switch User Manual
Priority 5 is assigned to the Switch's Q5 queue.
Priority 6 is assigned to the Switch's Q6 queue.
Priority 7 is assigned to the Switch's Q6 queue.
NOTE: In the DES-3528/DES-3552 Series, the Q7 is reserved for future use.
For strict priority-based scheduling, any packets residing in the higher priority queues are transmitted first. Multiple
strict priority queues empty based on their priority tags. Only when these queues are empty, are packets of lower
priority transmitted.
For weighted round robin queuing, the number of packets sent from each priority queue depends upon the assigned
weight. For a configuration of 8 CoS queues, A~H with their respective weight value: 8~1, the packets are sent in the
following sequence: A1, B1, C1, D1, E1, F1, G1, H1, A2, B2, C2, D2, E2, F2, G2, A3, B3, C3, D3, E3, F3, A4, B4, C4,
D4, E4, A5, B5, C5, D5, A6, B6, C6, A7, B7, A8, A1, B1, C1, D1, E1, F1, G1, H1.
For weighted round robin queuing, if each CoS queue has the same weight value, then each CoS queue has an equal
opportunity to send packets just like round robin queuing.
For weighted round-robin queuing, if the weight for a CoS is set to 0, then it will continue processing the packets from
this CoS until there are no more packets for this CoS. The other CoS queues that have been given a nonzero value,
and depending upon the weight, will follow a common weighted round-robin scheme.
Remember that the xStack
Service) for each port on the Switch.

HOL Blocking Pevention

This window is used to enable HOL Prevention Settings on the Switch.
To view this table click QoS > HOL Blocking Prevention
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DES-3528/DES-3552 Series of Switches has eight priority queues (and eight Classes of
Figure 5 - 2 HOL Blocking Prevention window
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