ATM Routing

Switch Administration

4.2.3Route Metrics

Route metrics are assigned to routes using a metric tag (one of the input parameters for add ATMRoute). The metric tag specifies a particular pair of incoming and outgoing metrics contained within a list of metrics. Metrics are created using the add PNNIMetric command. Each metric pair specifies a set of values that describe a route’s Service Category, cell rates, bandwidth, and administrative weight. Locally, metric values determine the behavior of the link, while network-wide, PNNI’s Generic Call Admission Control (GCAC) assesses metrics when establishing calls.

In the following example, a metric pair is created (with metric tag of nine) that specifies CBR as the Service Category, administrative weight of 200, Max Cell Rate of 1000 cells per second, and an Available Cell Rate of 750 cells per second.

First, we create the outgoing member of the metric pair:

SmartSwitch # add pnnimetrics

 

 

MetricsTag(1)

: 9

 

TrafficDirection(Outgoing)

:

< 1st pair member, we accept the default

ServiceCategory(UBR)

: cbr

 

GCAC_CLP(2)

:

 

AdminWeight(5040)

: 200

 

MaxCellRate(-1)

: 1000

 

AvailableCellRate(-1)

: 750

 

MaximumCellTransferDelay(-1)

:

 

CellDelayVariation(-1)

:

 

CellLossRatioForCLP=0(-1)

:

 

CellLossRatioForCLP=0+1(-1)

:

 

CellRateMargin(-1)

:

 

VarianceFactor(-1)

:

 

Next, we create the incoming member of the metric pair:

SmartSwitch # add pnnimetrics

 

MetricsTag(1)

: 9

TrafficDirection(Outgoing)

: incoming < 2nd pair member, we set as incoming

ServiceCategory(UBR)

: cbr

GCAC_CLP(2)

:

AdminWeight(5040)

: 200

MaxCellRate(-1)

: 1000

AvailableCellRate(-1)

: 750

MaximumCellTransferDelay(-1)

:

CellDelayVariation(-1)

:

CellLossRatioForCLP=0(-1)

:

CellLossRatioForCLP=0+1(-1)

:

CellRateMargin(-1)

:

VarianceFactor(-1)

:

SmartSwitch #

 

4-6 SmartSwitch 9A100 User Guide

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Image 48
Cabletron Systems 9A100 manual Route Metrics