Web Management Guide-R04

Chapter 9 | Class of Service
Layer 3/4 Priority Settings
– 262 –
Mapping Internal
DSCP Values to
Egress CoS Values
Use the Traffic > Priority > DSCP to CoS page to map internal per-hop behavior and
drop precedence value pairs to CoS values used in tagged egress packets on a
Layer 2 interface.
Command Usage
◆ Enter any per-hop behavior and drop precedence pair within the internal
priority map, and then enter the corresponding CoS/CFI pair.
◆ If the packet is forwarded with an 8021.Q tag, the priority value in the egress
packet is modified based on the default values shown in Table 18 on page 262,
or on the values modified by this function.
Parameters
These parameters are displayed in the web interface:
◆ Port – Port identifier.
◆ PHB – Per-hop behavior, or the priority used for this router hop. (Range: 0-7)
◆ Drop Precedence – Drop precedence used for controlling traffic congestion.
(Range: 0 - Green, 3 - Yellow, 1 - Red)
◆ CoS – Class-of-Service value. (Range: 0-7)
◆ CFI – Canonical Format Indicator. Set to this parameter to “0” to indicate that
the MAC address information carried in the frame is in canonical format.
(Range: 0-1)
Table 18: Mapping Internal PHB/Drop Precedence to CoS/CFI Values
Drop Precedence
Per-hop Behavior
0 (green) 1 (red) 3 (yellow)
0 (0,0) (0,0) (0,0)
1 (1,0) (1,0) (1,0)
2 (2,0) (2,0) (2,0)
3 (3,0) (3,0) (3,0)
4 (4,0) (4,0) (4,0)
5 (5,0) (5,0) (5,0)
6 (6,0) (6,0) (6,0)
7 (7,0) (7,0) (7,0)