Specifications

May 09, 2011 Page 1 of 38
Configuring Quality of Service (QoS)
ThischapterprovidesthefollowinginformationaboutconfiguringandmonitoringQualityof
Service(QoS)onEnterasys
®
N‐Series,S‐Series
®
,andK‐Seriesmodularswitches,A‐Series,
B‐Series,C‐Seriesstackablefixedswitches,andD‐Series,G‐Series,and I‐Seriesstandalonefixed
switches.
What Is Quality of Service?
QualityofService(QoS)is:
•Amechanismforthemanagementofbandwidth
•Theabilitytogivepreferentialtreatmenttosomepacketsoverothers
•Baseduponpacketclassificationandforwardingtreatment
Youconfigurepacketpreferenceandforwardingtreatmentbaseduponaflow’ssensitivityto
delay,delayvariation(jitter),bandwidth,availability,andpacketdrop.
QoS
usespacketpriority,inconjunctionwithqueuetreatmentconfiguration,todeterminethe
interface’sinboundandforwardingbehaviorforapacket.Packetpreferenceandforwarding
treatmentforagivenflowcanbeapplied torolesconfiguredinEnterasyspolicy.
Note: Please see the Enterasys X Secure Core Router Configuration Guide for a complete
discussion of QoS as it applies to the X-Series.
For information about... Refer to page...
What Is Quality of Service? 1
Why Would I Use It in My Network? 2
How Can I Implement Quality of Service? 2
Quality of Service Overview 2
CoS Hardware Resource Configuration 13
Feature Differences by Platform 28
The QoS CLI Command Flow 29
QoS Policy-Based Configuration Example 31
Terms and Definitions 36
Note: A flow is a stream of IP packets in which the value of a fixed set of IP packet fields is the
same for each packet in the stream. Each packet containing the same value for all of these fields is
considered part of the same flow, until flow expiration occurs. If a packet is viewed with any set
member field value that is different from any current flow, a new flow is started based upon the set
field values for that packet.