ATM and Layer 3 Switch Router Software Configuration Guide, 12.1(12c)E1
Configuring Resource Management
Download this chapter
Configuring Resource ManagementConfiguring Resource Management
Download the complete book
ATM and Layer 3 Switch Router Software Configuration GuideATM and Layer 3 Switch Router Software Configuration Guide (PDF - 10 MB)
give_us_feedback

Table of Contents

Configuring Resource Management
 Resource Management Functions
 Switch Fabric Functionality (Catalyst 8540 MSR)
 Processor Feature Card Functionality (Catalyst 8510 MSR and LightStream 1010)
 Configuring Global Resource Management
Configuring the Default QoS Objective Table
 Configuring the Switch Oversubscription Factor (Catalyst 8510 MSR and LightStream 1010)
 Configuring the Service Category Limit (Catalyst 8510 MSR and LightStream 1010)
 Configuring the ABR Congestion Notification Mode (Catalyst 8510 MSR and LightStream 1010)
 Configuring the Connection Traffic Table
 CTT Row Allocations and Defaults
 Configuring the Sustainable Cell Rate Margin Factor
 Overview of Threshold Groups
Configuring Physical Interfaces
 Configuring Physical and Logical Interface Parameters
 Configuring Interface Overbooking
 Configuring Framing Overhead

Configuring Resource Management

This chapter describes resource management, which involves modeling and managing switch, interface, and connection resources. Such resources include equivalent bandwidth and buffering to support the provision of specified traffic classes.

Note   This chapter provides advanced configuration instructions for the Catalyst 8540 MSR, Catalyst 8510 MSR, and LightStream 1010 ATM switch routers. For detailed descriptions of traffic management mechanisms and their operation, refer to the . For complete descriptions of the commands mentioned in this chapter, refer to the

This chapter includes the following sections:

Resource Management Functions

The ATM switch router resource management software provides the following functions:

  • Network management interface—Includes operational configuration changes (take place immediately), proposed configuration changes (take place on restart), user interface, and status.
  • Default quality of service (QoS) objective table management—Since User-Network Interface 3 (UNI 3) signalling does not provide information elements to signal QoS values, resource management provides a table that contains default values for QoS.
  • Connection Traffic Table (CTT) management—Rather than store traffic parameters for each connection in that connection's data structure, resource management manages a table of connection traffic parameters, used by network and connection management.
  • Hardware resource management (Catalyst 8540 MSR)—The switch processor feature card provides functionality that include statistic collection, and traffic policing usage parameter control (UPC). See Configuring Global Resource Management for detailed information.
  • Hardware resource management (Catalyst 8510 MSR and LightStream 1010)—Different sets of functionality are available with feature card per-class queueing (FC-PCQ) and feature card per-flow queueing (FC-PFQ). FC-PCQ features include switch cell priority limits, interface queue sizes, and thresholds. FC-PFQ features include threshold group configuration. The interface pacing feature is available with both feature cards. See Processor Feature Card Functionality (Catalyst 8510 MSR and LightStream 1010) for detailed information.
  • Resource Call Admission Control (RCAC)—Determines whether a virtual channel connection/virtual path connection (VCC/VPC) can be admitted (allowed to be set up), based on the available connection resources and requested traffic characteristics.
  • Logical interface creation and deletion.
  • Private Network-Network Interface (PNNI) metrics—resource management supplies PNNI with link metrics for connection routing.

Switch Fabric Functionality (Catalyst 8540 MSR)

The switch fabric for the Catalyst 8540 MSR provides the required ATM Forum Traffic Management features as described in Table 8-1.

Table 8-1   Switch Processor Feature Card

Feature  Description 

Traffic classes:

CBR1, VBR-RT2, VBR-NRT3, UBR4, ABR5(EFCI)6

Output queuing

Per-VC or per-VP

Output scheduling

RS7 and WRR8

Intelligent early packet discard

Multiple dynamic thresholds

Intelligent tail (partial) packet discard

Supported

Selective cell marking and discard

Multiple, weighted, dynamic thresholds

Shaping

Per-port pacing, per-CBR VC, per-CBR transit VP, per-shaped CBR VP tunnel (128 shaped VP tunnels total), and hierarchical VP tunnels

Policing (UPC9)10

Dual leaky bucket

Frame mode VC-merge

Supported

Point-to-multipoint VC (multicast)

Multiple leafs per output port, per point-to-multipoint

Network clock switchover10

Programmable clock selection criteria

Nondisruptive snooping

Per-VC or per-VP

Hierarchical VP tunnel

Maximum of 240 VP tunnels.
1 CBR = constant bit rate

2 VBR-RT = variable bit rate real time

3 VBR-NRT = variable bit rate non-real time

4 UBR = unspecified bit rate

5 ABR = available bit rate

6 EFCI = explicit forward congestion indication

7 RS = rate scheduling

8 WRR = weighted round-robin

9 UPC = usage parameter control

10 Performed by feature card

Processor Feature Card Functionality (Catalyst 8510 MSR and LightStream 1010)

Two types of feature cards are available for the Catalyst 8510 MSR and LightStream 1010 ATM switch routers: FC-PCQ and FC-PFQ. Each card provides the required ATM Forum Traffic Management features. FC-PCQ contains a subset of the FC-PFQ features, as described in Table 8-2.

Note   To determine which feature card you have installed, enter the show hardware EXEC command. Either FeatureCard1, for FC-PCQ, or FC-PFQ displays in the Ctrlr-Type column.

Table 8-2   FC-PCQ and FC-PFQ Feature Comparison

Feature  FC-PCQ  FC-PFQ 

Traffic classes

CBR1, VBR-RT2, VBR-NRT3, ABR4 (EFCI5 and RR6), UBR7

CBR, VBR-RT, VBR-NRT, ABR (EFCI and RR), UBR

Output queuing

Four classes per port

Per-VC or per-VP

Output scheduling

SP8

RS9 and WRR10

Intelligent early packet discard

Multiple fixed thresholds

Multiple dynamic thresholds

Intelligent tail (partial) packet discard

Supported

Supported

Selective cell marking and discard

Multiple fixed thresholds

Multiple, weighted, dynamic thresholds

Shaping

Per-port (pacing)

Per-port pacing, per-CBR VC, per-CBR transit VP, per-shaped CBR VP tunnel (128 shaped VP tunnels total), and hierarchical VP tunnels

Policing (UPC11)

Dual mode, single leaky bucket

Dual leaky bucket

Point-to-multipoint VC (multicast)

One leaf per output port, per point-to-multipoint

Multiple leafs per output port, per point-to-multipoint

Network clock switch over

Automatic upon failure

Programmable clock selection criteria

Nondisruptive snooping

Per-port transmit or receive

Per-VC or per-VP

Hierarchical VP tunnel12

-

Maximum of 62 VP tunnels
1 CBR = constant bit rate

2 VBR-NT = variable bit rate real time

3 VBR-NRT = variable bit rate non-real time

4 ABR = available bit rate

5 EFCI = explicit forward congestion indication

6 RR = relative rate

7 UBR = unspecified bit rate

8 SP = strict priority

9 RS = rate scheduling

10 WRR = weighted round-robin

11 UPC = usage parameter control

12 Available with FC-PFQ only

Configuring Global Resource Management

Global resource management configurations affect all interfaces on the switch. The following sections describe global resource management tasks:

Configuring the Default QoS Objective Table

Resource management provides a table of default objective values for quality of service (QoS) for guaranteed service categories. These values—either metrics or attributes—are used as the criteria for connection setup requirements.

Note   Default objective values for QoS for guaranteed service categories can be configured for UNI 4.0 signalling.

Table 8-3 lists the default values of the QoS objective table.

Table 8-3   Default QoS Objective Table Row Contents

Service
Category 		 Max Cell Transfer
Delay (clp01) 		 Peak-to-Peak Cell Delay Variation (clp01)  Cell Loss
Ratio (clp0) 		 Cell Loss Ratio
(clp0+1) 

CBR

Undefined

Undefined

Undefined

Undefined

VBR-RT

Undefined

Undefined

Undefined

Undefined

VBR-NRT

—

—

Undefined

Undefined

Each objective can have a defined or undefined value. If undefined, the objective is not considered in connection setup. The table should be configured with the same values for an entire network.

To configure the default QoS objective table, perform the following tasks in global configuration mode:

  Command  Purpose 
Step 1 

Switch(config)# atm qos default {cbr | vbr-rt} max-cell-transfer-delay {microseconds | any}

Selects the ATM QoS default CBR or VBR-RT maximum cell transfer delay.
Step 2 

Switch(config)# atm qos default {cbr | vbr-rt} peak-to-peak- cell-delay variation {microseconds | any}

Selects the ATM QoS default CBR or VBR-RT peak-to-peak cell delay variation.
Step 3 

Switch(config)# atm qos default {cbr | vbr-rt | vbr-nrt} max-cell-loss-ratio [clp0 | clp1plus0] {loss-ratio-exponent | any}

Selects the ATM QoS default CBR, VBR-RT, or VBR-NRT maximum cell loss ratio.
Example

The following example shows how to change the constant bit rate (CBR) maximum cell loss ratio objective for cell loss priority (CLP) = 0+1 to 10-12 cells per second:

Switch(config)# atm qos default cbr max-cell-loss-ratio clp1plus0 12

Displaying the ATM QoS Objective Table

To display the default QoS objective table, use the following EXEC command:

Command  Purpose 

show atm qos-defaults

Displays the ATM QoS objective table configuration.

The per-service category, maximum cell transfer delay, peak-to-peak cell delay variation, and maximum cell loss ratio objectives are displayed.

Example

The ATM QoS objective table configuration is displayed in the following example:

Switch> show atm qos-defaults
Default QoS objective table:
    Max cell transfer delay (in microseconds): any cbr, any vbr-rt
    Peak-to-peak cell  delay variation (in microseconds): any cbr, any vbr-rt
    Max cell loss ratio for CLP0 cells: any cbr, any vbr-rt, any vbr-nrt
    Max cell loss ratio for CLP0+1 cells:  10**(-12) cbr, any vbr-rt, any vbr-nrt

Configuring the Switch Oversubscription Factor (Catalyst 8510 MSR and LightStream 1010)

The switch oversubscription factor (OSF) feature on the Catalyst 8510 MSR and LightStream 1010 ATM switch routers is used in determining initial port maximum queue sizing for variable bit rate non-real time (VBR-NRT) and available bit rate/unspecified bit rate (ABR/UBR) queues.

Note   Over subscription factor configuration is only possible on switches with FC-PCQ installed.

The size of the VBR-NRT queue and ABR/UBR queues is determined by the following equations, where the default size of the CBR and VBR-RT queues vary by interface type, as listed in Table 8-4:

Default Size (VBR-NRT) = 0.25 * ((OSF * 2048) - DefaultSize(CBR) - DefaultSize (VBR-RT))
Default Size (ABR-UBR) = 0.75 * ((OSF * 2048) - DefaultSize(CBR) - DefaultSize (VBR-RT))

Table 8-4   Default CBR and VBR Determined by Interface Type

Interface Type  Default Max Size CBR Queue   Default Max Size Type
VBR-RT Queue 

SONET

256

256

DS3/E3

256

512

To configure the OSF, use the following global configuration command:

Command  Purpose 

atm over-subscription-factor o-value

Configures the switch OSF from 1 to 32.
Note   This value can be changed at any time, but it is only used at start-up and when a module is hot-swapped from the chassis.
Example

The following example shows how to set the switch oversubscription factor to 16:

Switch(config)# atm over-subscription-factor 16

Displaying the OSF Configuration (Catalyst 8510 MSR and LightStream 1010)

To display the OSF configuration, use the following EXEC command:

Command  Purpose 

show atm resource

Displays the OSF configuration.
Note   The following examples differ depending on the feature card installed in your switch.
Examples

The following example shows the switch OSF configuration with FC-PCQ installed:

Switch> show atm resource
Resource configuration:
    Over-subscription-factor 16  Sustained-cell-rate-margin-factor 1%
    Abr-mode:   relative-rate
    Atm service-category-limit (in cells):
         64544 cbr 64544 vbr-rt 64544 vbr-nrt 64544 abr-ubr
Resource state:
    Cells per service-category:
         0 cbr 0 vbr-rt 0 vbr-nrt 0 abr-ubr

Configuring the Service Category Limit (Catalyst 8510 MSR and LightStream 1010)

The service category limit configuration restricts the number of cells admitted into the switch, as determined by the type of output queues.

Note   Service category limit configuration is only possible on switches with FC-PCQ installed.
Caution    Setting a service category limit to 0 causes the connection requests for the associated service categories to be rejected.

To configure the service category limits, use the following global configuration command:

Command  Purpose 

atm service-category-limit {cbr | vbr-rt | vbr-nrt | abr-ubr} value

Configures ATM service category limits for a specific output queue.
Note   The atm service-category-limit command affects all connections, including those already established.
Example

The following example shows how to change the service category limit for the CBR cells within the switch fabric to 3000 cells:

Switch(config)# atm service-category-limit cbr 3000

Displaying the Service Category Limit Configuration (Catalyst 8510 MSR and LightStream 1010)

To display the service category limit configuration, use the following EXEC command:

Command  Purpose 

show atm resource

Displays the service category limits configuration.
Example

The following example shows the service category limits configuration:

Switch> show atm resource
Resource configuration:
    Over-subscription-factor 16  Sustained-cell-rate-margin-factor 1%
    Abr-mode:   relative-rate
    Atm service-category-limit (in cells):
         3000 cbr 64544 vbr-rt 64544 vbr-nrt 64544 abr-ubr
Resource state:
    Cells per service-category:
         0 cbr 0 vbr-rt 0 vbr-nrt 0 abr-ubr

Configuring the ABR Congestion Notification Mode (Catalyst 8510 MSR and LightStream 1010)

The available bit rate (ABR) congestion notification mode changes the type of notification used on ABR connections to alert the end station of congestion. ABR mode configuration determines whether ABR uses explicit forward congestion indication (EFCI) marking, relative-rate marking, or both, for rate management on ABR connections.

The global configuration function is used to modify the ABR mode selection for all ABR connections.

To configure the ABR mode, use the following global configuration command:

Command  Purpose 

atm abr-mode {efci | relative-rate | all}

Configures ABR congestion notification mode.
Note   The atm abr-mode command affects all connections, including those already established.
Example

The following example shows how to configure the entire switch to set the EFCI bit whenever a cell arrives on a congested ABR connection:

Switch(config)# atm abr-mode efci

Displaying the ABR Congestion Notification Mode Configuration (Catalyst 8510 MSR and LightStream 1010)

To display the ABR congestion notification mode configuration, use the following EXEC command:

Command  Purpose 

show atm resource

Displays the ABR congestion notification mode configuration.
Note   The following examples differ depending on the feature card installed in your switch.
Examples

The following example shows the ABR mode configuration with FC-PCQ installed:

Switch> show atm resource
Resource configuration:
    Over-subscription-factor 16  Sustained-cell-rate-margin-factor 1%
    Abr-mode: efci
    Atm service-category-limit (in cells):
         3000 cbr 64544 vbr-rt 64544 vbr-nrt 64544 abr-ubr
Resource state:
    Cells per service-category:
         0 cbr 0 vbr-rt 0 vbr-nrt 0 abr-ubr

The following example shows the ABR mode configuration with FC-PFQ installed:

Switch> show atm resource
Resource configuration:
    Over-subscription-factor 8  Sustained-cell-rate-margin-factor 1%
    Abr-mode:   efci
    Service Category to Threshold Group mapping:
     cbr 1 vbr-rt 2 vbr-nrt 3 abr 4 ubr 5
    Threshold Groups:
    Group Max    Max Q  Min Q  Q thresholds  Cell  Name
          cells  limit  limit  Mark Discard  count
          instal instal instal
    ---------------------------------------------------
     1    65535  63     63     25 %  87 %      0     cbr-default-tg
     2    65535  127    127    25 %  87 %      0     vbrrt-default-tg
     3    65535  511    31     25 %  87 %      0     vbrnrt-default-tg
     4    65535  511    31     25 %  87 %      0     abr-default-tg
     5    65535  511    31     25 %  87 %      0     ubr-default-tg
     6    65535  1023   1023   25 %  87 %      0     well-known-vc-tg

Configuring the Connection Traffic Table

A row in the connection traffic table (CTT) must be created for each unique combination of traffic parameters. Virtual path links (VPLs) and virtual channel links (VCLs) then specify traffic by specifying a row in the table per flow (receive and transmit). Many VCL/VPLs can refer to the same row in the traffic table.

The following two subsections outline the differences in the CTT feature according to platform and feature card.

CTT Supported Features (Catalyst 8540 MSR)

The rows corresponding to various service categories support the following features on the Catalyst 8540 MSR.

  • Non-zero minimum cell rate (MCR) for UBR+ service categories. UBR+ is a variant of UBR, in which peak cell rate (PCR), MCR, and cell delay variation tolerance (CDVT) are specified in the traffic contract, with a guarantee on MCR.
  • Both CDVT and maximum burst size (MBS) for VBR rows. Dual-leaky-bucket UPC is allowed.
  • Whether SCR applies to either the CLP0 or CLP0+1 flow of cells. Only one or the other of these flows can be policed.

CTT Supported Features (Catalyst 8510 MSR and LightStream 1010)

ATM switch routers with feature card per-flow queuing (FC-PFQ) and software version 11.2(8) or later have more rows of various service categories that allow you to specify the following features:

  • Non-zero minimum cell rate (MCR) for ABR and UBR+ service categories. UBR+ is a variant of UBR, in which peak cell rate (PCR), MCR, and cell delay variation tolerance (CDVT) are specified in the traffic contract, with a guarantee on MCR.
  • Both CDVT and maximum burst size (MBS) for VBR rows. FC-PFQ allows dual-leaky-bucket UPC.
  • Whether SCR applies to either the CLP0 or CLP0+1 flow of cells. FC-PFQ can police one or the other of these flows.

If your switch has FC-PCQ installed on the route processor you cannot take advantage of these new capabilities. CTT rows specifying these new parameters can be configured with FC-PCQ installed, with the following effect:

  • Non-zero MCR is not supported. Requests for connections specifying non-zero MCR are rejected.
  • On VBR connections, only SCR and MBS are used for UPC, and policing is done only on the CLP0+1 flow of cells.

PVC Connection Traffic Rows

The CTT in a permanent virtual channel (PVC) setup requires storing PVC traffic values in a CTT data structure. Rows used for PVCs are called stable rows, and contain traffic parameters.

SVC Connection Traffic Rows

The CTT in a switched virtual channel (SVC) setup provides a row identifier that Simple Network Management Protocol (SNMP) or the user interface can use to read or display SVC traffic parameters. A CTT row index is stored in the connection-leg data structure for each flow of the connection.

Note   Rows cannot be deleted while in use by a connection.

CTT Row Allocations and Defaults

To make CTT management software more efficient, the CTT row-index space is split into rows allocated as a result of signalling and rows allocated from the command-line interface (CLI) and SNMP. Table 8-5 describes the row-index range for both.

Table 8-5   CTT Row-Index Allocation

Allocated by  Row-index range 

ATOMMIB Traffic Descriptor Table or CLI connection-traffic-table-row creation

1 through 1,073,741,823

Signalling VxL creation

1,073,741,824 through 2,147,483,647

Table 8-6 describes the well-known, predefined ATM CTT rows.

Table 8-6   Default ATM Connection Traffic Table Rows

CTT Row
Index 		 Service
Category 		 Peak-Cell-Rate
(clp01) 		 Sustained-
Cell-Rate
(clp01) 		 Tolerance  Use 

1

UBR

7,113,539

—

None

Default PVP/PVC row index

2

CBR

424 kbps

—

None

CBR tunnel well-known (WK) VCs

3

VBR-RT

424 kbps

424 kbps

50

Physical interface/VBR-RT WK VCs

4

VBR-NRT

424 kbps

424 kbps

50

VBR-NRT tunnel WK VCs

5

ABR

424 kbps

—

None

—

6

UBR

424 kbps

—

None

UBR tunnel WK VCs

The atm connection-traffic-table-row command supports these service categories: CBR, VBR-RT, VBR-NRT, ABR, and UBR. To create or delete an ATM CTT row, perform the following tasks in global configuration mode:

Note   Your CTT feature set depends on the type of feature card that is installed on the Catalyst 8510 MSR and LightStream 1010 ATM switch routers route processor.

  Command  Purpose 
Step 1 

Switch(config)# atm connection-traffic-table-row [index row-index] {vbr-rt | vbr-nrt} pcr pcr-value {scr0 | scr10} scr-value [mbs mbs-value] [cdvt cdvt_value]

Configures an ATM CTT VBR row.
Step 2 

Switch(config)# atm connection-traffic-table-row [index row-index] cbr pcr pcr-value [cdvt cdvt-value]

Configures an ATM CTT CBR row.
Step 3 

Switch(config)# atm connection-traffic-table-row [index row-index] abr pcr pcr-value [mcr mcr-value] [cdvt cdvt-value]

Configures an ATM CTT ABR row.
Step 4 

Switch(config)# atm connection-traffic-table-row [index row-index] ubr pcr pcr-value [mcr mcr-value] [cdvt cdvt-value]

Configures an ATM CTT UBR row.

If you do not specify an index row number, the system software determines if one is free and displays it in the allocated index field if the command is successful.

Example

The following example shows how to configure an ATM CTT row with an ABR peak cell rate of 30,000 kbps:

Switch(config)# atm connection-traffic-table-row abr pcr 30000
 Allocated index = 63999

Displaying the ATM Connection Traffic Table

To display the CTT configuration, use the following EXEC command:

Command  Purpose 

show atm connection-traffic-table [row row-index | from-row row-index]

Displays the CTT configuration.
Example

The following example shows how to display the CTT configuration table:

Switch> show atm connection-traffic-table
Row      Service-category    pcr        scr/mcr       mbs         cdvt
1            ubr          7113539        none                     none
2            cbr              424                                 none
3            vbr-rt           424         424          50         none
4            vbr-nrt          424         424          50         none
5            abr              424           0                     none
6            ubr              424        none                     none
64000        cbr             1741                                 none
2147483645*  ubr                0        none                     none
2147483646*  ubr                1        none                     none
2147483647*  ubr          7113539        none                     none

Configuring the Sustainable Cell Rate Margin Factor

The sustained cell rate margin factor determines the aggressiveness of weighting sustainable cell rate (SCR) compared to peak cell rate (PCR). It uses the connection admission control algorithm in admitting VBR connections.

To configure the SCR for your ATM switch router, use the following global configuration command:

Command  Purpose 

atm sustained-cell-rate-margin-factor s-value

Configures the sustained cell rate margin factor.
Note   The atm sustained-cell-rate-margin-factor command affects subsequent connections but not connections that are already established.
Example

The following example shows how to configure the SCR margin factor as 85 percent of maximum:

Switch(config)# atm sustained-cell-rate-margin-factor 85

Displaying the SCR Margin Configuration

To display the SCR margin factor configuration, use the following EXEC command:

Command  Purpose 

show atm resource

Displays the SCR margin factor configuration.
Example

The following example shows the SCR margin factor configuration:

Switch> show atm resource
Resource configuration:
Sustained-cell-rate-margin-factor 85%
    Abr-mode:   EFCI
    Service Category to Threshold Group mapping:
     cbr 1 vbr-rt 2 vbr-nrt 3 abr 4 ubr 5
    Threshold Groups:
 Module   Group Max    Max Q  Min Q  Q thresholds  Cell  Name
  ID            cells  limit  limit  Mark Discard  count
                instal instal instal
 ------------------------------------------------------------
  1        1    131071  63     63     25 %  87 %      0     cbr-default-tg
           2    131071  127    127    25 %  87 %      0     vbrrt-default-tg
           3    131071  511    31     25 %  87 %      0     vbrnrt-default-tg
           4    131071  511    31     25 %  87 %      0     abr-default-tg
           5    131071  511    31     25 %  87 %      0     ubr-default-tg
           6    131071  1023   1023   25 %  87 %      0     well-known-vc-tg
===========================================================
  2        1    131071  63     63     25 %  87 %      0     cbr-default-tg
           2    131071  127    127    25 %  87 %      0     vbrrt-default-tg
           3    131071  511    31     25 %  87 %      0     vbrnrt-default-tg
           4    131071  511    31     25 %  50 %    &n