Beta Draft Confidential
12-4
1/19/05
ATM Services Configuration Guide for CBX 3500, CBX 500, GX 550, and B-STDX 9000
Configuring ATM Traffic Descriptors
About TDs
About Logical Port QoS Parameters
When you configure a logical port, you specify QoS parameters for each class of
service (CBR through ABR/UBR). For more information about configuring these
parameters, see
“Setting QoS Parameters” on page 3-51
. The following list
summarizes each of these parameters:
Bandwidth Allocation — Configures the amount of bandwidth to allocate on a
logical port. You can configure a fixed percentage of bandwidth, or enable the
bandwidth to change dynamically according to bandwidth demands.
Routing Metric — Optimizes network resources by routing traffic over the path that
best matches the QoS needs of the associated VC. By selecting one of these metrics,
you can ensure that a PVC, SVC, or SPVC originating from this logical port follows
an efficient routing path to its destination.
Oversubscription Factor — Enables you to provision more PVCs, SVCs, or SPVCs
on a given logical port than the amount of supported physical bandwidth. This ability
to “oversubscribe” a logical port’s bandwidth assumes that not all network resources
are in use at the same time. For more information about the oversubscription factor,
see
.
About Traffic Parameters
This section describes network traffic parameters and their associated ATM TD
combinations. When you create a logical port, PVC, or an SPVC, you can select a TD
that specifies how the network controls traffic going in the forward and reverse
direction on that entity. This TD is made up of individual traffic parameters which
work together to provide traffic shaping.
describes the individual traffic parameters.
Table 12-2.
Traffic Parameters
Traffic
Parameter
Description
CLP=0
Specifies the high-priority cell stream (cells whose cell loss priority bit
is set to zero [0]).
CLP=1
Specifies the low-priority cell stream (cells whose cell loss priority bit is
set to 1).
CLP=0+1
Specifies the aggregate cell stream (all cells in this circuit whose cell
loss priority bit is either 0 or 1).
PCR
PCR is the maximum allowed cell transmission rate (expressed in cells
per second [CPS]). It defines the shortest time period between cells and
provides the highest guarantee that network performance objectives
(based on cell loss ratio [CLR]) will be met.
Summary of Contents for CBX 3500
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