3Com 4007, Руководство по внедрению, Страница: 572 / 684

572 C
HAPTER
22: Q
O
S
AND
RSVP
■
QoS excess tagging — Allows you to select an IEEE 802.1p priority
tag value for nonconforming excess packets (packets that exceed the
rate limit). This option refers to any packets marked as excess that you
want to tag. After you enable this option, select an IEEE 802.1p
priority tag value in the range of from
0 through 7 (
0
is the default).
Specifying
1
makes nonconforming excess packets background traffic.
For nonflow classifiers only, IEEE 802.1P tag values range from 0
through 7. To allow low priority queues to get serviced and to
prevent starvation of best effort traffic in the low priority queue,
3Com has implemented the following map:
■
priorities 1-2 map to the low queue
■
priorities 0, 3 map to the best queue
■
priorities 4-7 map to the high queue
These are the defaults which you can change through modifying the
associated classifiers and controls. See classifiers 401 through 407 and
499 and associated controls 1 through 4, using the QoS CLASSIFIER
SUMMARY and QoS CONTROL SUMMARY commands respectively.