52-9
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
OL-8978-04
Chapter 52 Configuring QoS
Understanding How QoS Works
Figure 52-8
Ethernet Egress Port Scheduling, Congestion Avoidance, and Marking
Figure 52-9
Single-Port ATM OC-12 Switching Module Marking
68002
Write CoS
into
frame
ISL or
802.1Q?
IP traffic
from PFC?
Write ToS
byte into
packet
DSCP
rewrite
enabled?
No
No
No
Yes
Yes
Yes
Ethernet egress port scheduling, congestion avoidance, and marking
Transmit
frame
From switching
engine or MSFC
Drop thresholds
PFC3
only
27105
Transmit
cell
IP traffic
from PFC?
Write ToS
byte into
packet
No
Yes
Single-port ATM OC-12 switching module marking
From switching
engine or MSFC