Qos (Quality Of Service) - D-Link DES-3250TG User Manual

QOS (Quality of Service)

The DES-3250TG switch supports 802.1p priority queuing. The switch has four priority queues. These
priority queues are numbered from 0 — the lowest priority queue — to 3 — the highest priority queue.
The eight priority queues specified in IEEE 802.1p (Q0 to Q7) are mapped to the switch's priority
queues as follows:
Q2 and Q1 are assigned to the switch's Q0 queue.
Q3 and Q0 are assigned to the switch's Q1 queue.
Q5 and Q4 are assigned to the switch's Q2 queue.
Q7 and Q6 are assigned to the switch's Q3 queue.
The switch's four priority queues are emptied in a round-robin fashion—beginning with the highest
priority queue, and proceeding to the lowest priority queue before returning to the highest priority
queue.
For strict priority-based scheduling, any packets residing in the higher priority queues are transmitted
first. Only when these queues are empty, are packets of lower priority transmitted.
The weighted-priority based scheduling alleviates the main disadvantage of strict priority-based
scheduling − in that lower priority queues get starved of bandwidth − by providing a minimum
bandwidth to all queues for transmission. This is accomplished by configuring the maximum number of
packets allowed to be transmitted from a given priority queue and the maximum amount of time a given
priority queue will have to wait before being allowed to transmit its accumulated packets.
establishes a Class of Service (CoS) for each of the switch's four hardware priority queues.
The possible range for maximum packets is: 0 to 255 packets.
The possible range for maximum latency is: 0 to 255 (in increments of 16 microseconds each).
D-Link DES-3250TG Standalone Layer 2 Switch
Admin State
<Disabled>
Max Learning
Addr.(0-10) <1 >
Lock Address
Mode
<Delete On Reset>
Allows the selected port(s) dynamic
MAC address learning to be locked
such that new source MAC addresses
cannot be entered
address table for the locked port or
group of ports. It can be changed by
toggling between
Enabled.
Select the maximum
addresses that may be learned for the
port. The port can be restricted to 10
or less MAC addresses that are allowed
for dynamically
addresses in the forwarding table.
Select Delete On Timeout to clear
dynamic entries for the ports on
timeout of the Forwarding Data Base
(FDB). Specify Delete On Reset to delete
all FDB entries, including static entries
upon system reset or rebooting.
70
into the MAC
Disabled and
number of
learned MAC
This