Cisco BPX 8650, Installation And Configuration Manual

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 21 Configuring ATM Connections
Traffic Management Overview
The standard ATM traffic parameters are defined in Table 21-2.
The Quality of Service (QoS) parameters are defined in Table 21-3.
For congestion control feedback, ABR provides a means to control flow based on congestion
measurement.
QoS Parameters
Pk-to-Pk CDV x x
Max CTD x x
CLR x x x nw specific
Other Attributes
Congestion Control Feedback x
Table 21-1 Standard ATM Traffic Classes (continued)
Attribute CBR rt-VBR nrt-VBR UBR ABR
Table 21-2 Traffic Parameters
Name Description
PCR Defines the Peak Cell Rate (PCR) in cells per second. The maximum rate at which
a connection can transmit.
CDVT Defines the Cell Delay Variation Tolerance (CDVT) in usec. The time scale is
established over which the PCR is policed. The time scale is set to allow for jitter
(CDV) that is introduced, for example, by upstream nodes.
MBS Defines the Maximum Burst Size (MBS) in cells. The maximum number of cells
can burst at the PCR but still be compliant. This is used to determine the Burst
Tolerance (BT,) which controls the time scale over which the Sustained Cell Rate
(SCR) is policed.
MCR Defines the Minimum Cell Rate (MCR) in cells per second. The minimum cell is
rated to contract delivery by the network.
Table 21-3 Quality of Service Parameters
Name Description
CDV Specifies the Cell Delay Variation (CDV) that determines the measure for the cell
jitter introduced by network elements.
Max CTD Specifies the Maximum Cell Transfer Delay (Max CTD) that determines the
maximum delay incurred by a cell, such as propagation and buffering delays.
CLR Specifies the Cell Loss ratio (CLR) that determines the percentage of lost
transmitted cells.