Beta Draft Confidential
Configuring CBX or GX Logical Ports
QoS Attributes
ATM Services Configuration Guide for CBX 3500, CBX 500, GX 550, and B-STDX 9000 1/19/053-51
QoS Attributes
The QoS tab allows you to set the Quality of Service (QoS) parameters for a logical 
port.
Setting QoS Parameters
This section describes how to set the (QoS) parameters for a logical port. These 
parameters enable you to specify the bandwidth and routing metrics (if applicable) for 
the various traffic service classes. Lucent recommends that you set the logical port 
QoS fixed and dynamic options before you provision circuits. Under certain 
conditions, if you change the bandwidth from dynamic to fixed after you provision 
circuits, one or more QoS classes (including CBR) may display negative bandwidth. 
For more information about QoS, see “About QoS” on page 12-3. 
Table 3-8 lists the default QoS parameters. The switch routes circuits depending on 
the logical port routing metric you select.
Table 3-8. Default QoS Values for ATM UNI Logical Ports
Service Type Bandwidth 
Allocation
Routing Metric Oversubscription 
Factor
CBR/CFR Dynamic Admin Cost 100%
VBR/VFR (RT) Dynamic Admin Cost 100%
VBR/VFR (NRT) Dynamic Admin Cost 100%
ABR/UBR Dynamic Admin Cost 100%