Configuring Quality Of Service; Vpt Classification Information - D-Link DES-3010PA - Switch Web User Manual

Section 16. Configuring Quality of Service
Quality of Service (QoS) provides the ability to implement QoS and priority queuing within a network. For example,
certain types of traffic that require minimal delay, such as Voice, Video, and real-time traffic can be assigned a
high priority queue, while other traffic can be assigned a lower priority queue. The result is an improved traffic flow
for traffic with high demand. QoS is defined by:
•
Classification — Specifies which packet fields are matched to specific values. All packets matching the user-
defined specifications are classified together.
•
Action — Defines traffic management, where packets are
packet field values, such

VPT Classification Information

VLAN Priority Tags (VPT) are used to classify packets by mapping packets to one of the egress queues.
VPT-to-queue assignments are user-definable. Packets arriving untagged are assigned a default VPT value,
which is set on a per-port basis. The assigned VPT is used to map the packet to the egress queue. The table
below details the VPT-to-queue default settings:
Table 14: CoS to Queue Mapping Table Default values
C o S Val u e
0
1
2
3
4
5
6
7
DSCP values can be mapped to priority queues. DSCP mapping is enabled on a per-system basis. The following
table contains the default DSCP mapping to egress queue values:
Table 15: DSCP to Queue Mapping Table Default Values
D S C P Val ue
0-15
16-31
32-47
48-63
as VLAN Priority Tag (VPT) and DiffServ Code Point (DSCP).
F orw a r di ng Q u e ue Val ue s
q1 (Lowest Priority)
q0 (Lowest Priority)
q0 (Lowest Priority)
q1 (Lowest Priority)
q2
q2
q3
q3
F orw a r di ng Q u e ue Val ue s
q1 (Lowest Priority)
q2
q3
q4
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Configuring Quality of Service

VPT Classification Information
forwarded based on packet information and