Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 985)

Quality of Service (QoS) Introduction
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 38.13
CoS tagging commands
Table 38-3 shows the commands you can use to change the CoS field within incoming
packets.
Mapping CoS tags to traffic types
The command mls qos map cos-queue to enables you to create a switch-wide mapping
of CoS values to egress queues. The default mappings for this command are:
COS : 0 1 2 3 4 5 6 7
--------------------------------
QUEUE: 2 0 1 3 4 5 6 7
These mappings match the CoS guidelines documented in Annex H.2 of ANSI/IEEE 802.1D
1988 Edition. Table H-15 on page 355 of the standard shows a table of user priorities for
specific traffic types.
Table 38-4 shows an adapted version of the ANSI/IEEE table.
Table 38-3: CoS Mapping Commands in Hierarchical Order
Command Function
mls qos map premark-
dscp to Where a packet contains CoS tag and a DSCP tag. The
table set by this command contains a configurable
DSCP to CoS tag mapping.
remark-map Configures the remark map. This command is applied
when a policer is configured with the action parameter
of the command
police twin-rate action set to remark-
transmit.
Note Where a packet contains both a CoS and a DSCP field, and each field maps to a
different class-map; the switch will apply a priority that is based on the date
that the class-map was added to the policy-map; the earlier the date, the higher
the priority.
Table 38-4: Traffic Type Guidelines
User Priority
(egress
queue) CoS
Value
Acronym Traffic type Internal Traffic
Queue Defaults
0 (lowest) 1 BK Background
1 2 - Spare
2 0 BE Best Effort Default
3 3 EE Excellent Effort
4 4 CL Controlled Load
5 5 VI “Video,” <100 ms
latency and jitter
6 6 VO “Voice,” <10 ms
latency and jitter EPSR-Management
BPDU
ARP-Requests
7 (highest) 7 NC Network Control Stack Management