Metering Overview - Nortel business policy switch 2000 User Manual

Chapter 4 Policy-enabled networks 301

Metering overview

QoS metering, which operates at ingress, provides different levels of service to
data streams through user-configurable parameters. A meter is used to measure
the traffic stream against a traffic profile, which you create. Thus, creating meters
yields In-Profile and Out-of-Profile traffic.
Beginning with software version 2.0, you no longer need to configure a meter if
you are not metering data.
Using meters, you set a Committed Rate in Kb/s (1000 bits per second in each
Kb/s). All traffic within this Committed Rate is In-Profile. Additionally, you set a
Maximum Burst Rate that specifies an allowed data burst larger than the
Committed Rate for a brief period. After you set the Maximum Burst Rate, the
system helps you choose the Duration for this burst. Combined, these parameters
define the In-Profile traffic.
An example of traffic policing is limiting traffic entering a port to a specified
bandwidth, such as 25 Kb/s (Committed Rate). Instead of dropping all traffic that
exceeds this threshold, you can configure a Maximum Burst Rate to exceed the
threshold (Committed Rate), for a brief period of time (Duration), without being
dropped.
Note: Burst rate and duration are used to determine burst size.
You can also configure policies without metering. In this case, using the
Web-based management system, you choose No Meter Data in the Data
Specification field of the Meter page. Refer to Using Web-based Management for
the Business Policy Switch 2000 Software Version 2.0 for more information using
the Web-based management system to configure QoS parameters on the BPS
2000.
Using the Business Policy Switch 2000 Version 2.0