Extreme 3804 User Guide

8-2

S

UMMIT

 S

WITCH

 I

NSTALLATION

 

AND

 U

SER

 G

UIDE

Q

UALITY

 

OF

 S

ERVICE

 (Q

O

S)

QoS profiles are assigned to traffic classifications, independent of the QoS mode chosen, 
in order to modify switch forwarding behavior.

There are two modes of QoS. Ingress mode, the default, can use a wide variety of traffic 
classifications, but has a limitation of being able to use only the default four QoS 
profiles. You can modify the bandwidth parameters of the default QoS profiles.

Using egress mode, you can define additional QoS profiles, but you must use a smaller 
selection of traffic classifications. You can modify both the prioritization and bandwidth 
parameters of user-defined QoS profiles.

Four default QoS profiles are provided that cannot be deleted. The default QoS profile 
names are as follows:

qp1

qp2

qp3

qp4

The default QoS profiles exist in either ingress or egress mode. In ingress mode, only 
the default QoS profiles are observed. In egress mode, up to 28 additional custom 
profiles may be defined, for a total of 32. You cannot create custom profiles in ingress 
mode.

The parameters that make up a QoS profile include the following:

 — The minimum percentage of bandwidth that the traffic 

requires. The switch is required to provide the minimum amount of bandwidth to 
the traffic. The lowest possible value is 0%.

 — The maximum percentage of bandwidth that the traffic is 

permitted to use.

 — The level of priority in which the traffic will be serviced by the switch. 

Choices include:

Low

Normal

Summit.bk : 8QOS.FM  Page 2  Thursday, June 18, 1998  9:27 AM