Mapping Cos Priorities To Internal Dscp Values - Edge-Core ECS3510-10PD Management Manual

To show the DSCP to internal PHB/drop precedence map:
Click Traffic, Priority, DSCP to DSCP.
1.
Select Show from the Action list.
2.
Select a port.
3.
Figure 135: Showing DSCP to DSCP Internal Mapping
Use the Traffic > Priority > CoS to DSCP page to maps CoS/CFI values in
M C S
APPING O
incoming packets to per-hop behavior and drop precedence values for
P
RIORITIES TO
priority processing.
I DSCP
NTERNAL
V
ALUES
CLI R
◆ "qos map cos-dscp" on page 1178
C
OMMAND
The default mapping of CoS to PHB values is shown in
◆
page
Enter up to eight CoS/CFI paired values, per-hop behavior and drop
◆
precedence.
If a packet arrives with a 802.1Q header but it is not an IP packet, then
◆
the CoS/CFI-to-PHB/Drop Precedence mapping table is used to
generate priority and drop precedence values for internal processing.
Note that priority tags in the original packet are not modified by this
command.
The internal DSCP consists of three bits for per-hop behavior (PHB)
◆
which determines the queue to which a packet is sent; and two bits for
drop precedence (namely color) which is used by Random Early
Detection (RED) to control traffic congestion.
◆ RED starts dropping yellow and red packets when the buffer fills up to
16 packets on Fast Ethernet ports and 72 packets on Gigabit Ethernet
EFERENCES
U
SAGE
286.
– 285 –
| Class of Service
C 10
HAPTER
Layer 3/4 Priority Settings
Table 18 on