Table of Contents

Configuring Virtual Connections

This chapter describes how to configure virtual connections (VCs) in a typical ATM network after autoconfiguration has established the default network connections. The network configuration modifications described in this chapter are used to optimize your ATM network operation.

Note   This chapter provides advanced configuration instructions for the Catalyst 8540 MSR, Catalyst 8510 MSR, and LightStream 1010 ATM switch routers. For an overview of virtual connection types and applications, refer to the . For complete descriptions of the commands mentioned in this chapter, refer to the publication.

The tasks to configure virtual connections are described in the following sections:

Characteristics and Types of Virtual Connections

This section lists the various virtual connections (VC) types in Table 6-1.

Configuring Virtual Channel Connections

This section describes configuring virtual channel connections (VCCs) on the ATM switch router. A VCC is established as a bidirectional facility to transfer ATM traffic between two ATM layer users. Figure 6-1 shows an example VCC between ATM user A and user D.

An end-to-end VCC, as shown in Figure 6-1 between user A and user D, has two parts:

The common endpoint between an internal connection and a link occurs at the switch interface. The endpoint of the internal connection is also referred to as a connection leg or half-leg. A cross-connect connects two legs together.

Note   The value of the VPIs and VCIs can change as the traffic is relayed through the ATM network.

To configure a point-to-point VCC, perform the following steps, beginning in global configuration mode:

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Note   When configuring PVC connections, begin with lower VCI numbers. Using low VCI numbers allows more efficient use of the switch fabric resources.

Note   This parameter specifies the weight assigned to the output VC for weighted round robin scheduling and is an integer in the range of 1 to 15.This parameter is valid only on systems equipped with the switch processor feature card. (Catalyst 8540 MSR and Catalyst 8510 MSR and LightStream 1010 with FC-PFQ). For more information on scheduling, see "Scheduling Output" in the Guide to ATM Technology.

Note   The sched option is only available on OC-48c interfaces. Each OC-48c interface has four OC-12 schedulers. The sched variable is used to select the specific OC-12 scheduler for which the virtual circuit is assigned for output on an interface and is therefore a number between 1 and 4.

Examples

The following example shows how to configure the internal cross-connect PVC on Switch B between interface ATM 3/0/1 (VPI = 0, VCI = 50) and interface ATM 3/0/2 (VPI = 2, VCI = 100) (see Figure 6-1):

The following example shows how to configure the internal cross-connect PVC on Switch C between interface ATM 0/0/0, VPI = 2, VCI = 100, and interface ATM 0/0/1, VPI 50, VCI = 255:

Each subsequent VC cross-connection and link must be configured until the VC is terminated to create the entire VCC.

Note   The above examples show how to configure cross-connections using one command. This is the preferred method, but it is also possible to configure each leg separately, then connect them with the atm pvc vpi vci interface atm card/subcard/port vpi vci command. This alternative method requires more steps, but might be convenient if each leg has many additional configuration parameters or if you have configured individual legs with SNMP commands and you want to connect them with one CLI command.

Displaying VCCs

To show the VCC configuration, use the following EXEC commands:

Note   The following examples differ depending on the feature card installed on the processor.

Examples

The following example shows the Switch B PVC configuration on ATM interface 3/0/1:

The following example shows the Switch B PVC configuration on ATM interface 3/0/1:

The following example shows the Switch B PVC configuration on ATM interface 3/0/1, VPI = 0, VCI = 50, with the switch processor feature card installed:

Deleting VCCs from an Interface

This section describes how to delete a VCC configured on an interface. To delete a VCC, perform the following steps, beginning in global configuration mode:

Example

The following example shows how to delete the VCC on ATM interface 3/0/0, VPI = 20, VCI = 200:

Confirming VCC Deletion

To confirm the deletion of a VCC from an interface, use the following EXEC command before and after deleting the VCC:

Example

The following example shows how to confirm that the VCC is deleted from the interface:

Configuring Terminating PVC Connections

This section describes configuring point-to-point and point-to-multipoint terminating permanent virtual channel (PVC) connections. Terminating connections provide the connection to the ATM switch router's route processor for LAN emulation (LANE), IP over ATM, and control channels for Integrated Local Management Interface (ILMI), signalling, and Private Network-Network Interface (PNNI) plus network management.

Figure 6-2 shows an example of transit and terminating connections.

Point-to-point and point-to-multipoint are two types of terminating connections. Both terminating connections are configured using the same commands as transit connections (discussed in the previous sections). However, all switch terminating connections use interface atm0 to connect to the route processor.

Note   Since release 12.0(1a)W5(5b) of the system software, addressing the interface on the processor (CPU) has changed. The ATM interface is now called atm0, and the Ethernet interface is now called ethernet0. The old formats (atm 2/0/0 and ethernet 2/0/0) are still supported.

To configure both point-to-point and point-to-multipoint terminating PVC connections, perform the following steps, beginning in global configuration mode:

When configuring point-to-multipoint PVC connections using the atm pvc command, the root point is port A and the leaf points are port B.

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Note   This parameter specifies the weight assigned to the output VC for weighted round robin scheduling and is an integer in the range of 1 to 15.This parameter is valid only on systems equipped with the switch processor feature card. (Catalyst 8540 MSR and Catalyst 8510 MSR and LightStream 1010 with FC-PFQ). For more information on scheduling, see "Scheduling Output" in the Guide to ATM Technology.

Note   The sched option is only available on OC-48c interfaces. Each OC-48c interface has four OC-12 schedulers. The sched variable is used to select the specific OC-12 scheduler for which the virtual circuit is assigned for output on an interface and is therefore a number between 1 and 4.

Examples

The following example shows how to configure the internal cross-connect PVC between interface ATM 3/0/1, VPI = 1, VCI = 50, and the terminating connection at the route processor interface ATM 0, VPI = 0, and VCI unspecified:

The following example shows how to configure the route processor leg of any terminating PVC:

When configuring the route processor leg of a PVC that is not a tunnel, the VPI should be configured as 0. The preferred method of VCI configuration is to select the any-vci parameter, unless a specific VCI is needed as a parameter in another command, such as map-list.

Note   If configuring a specific VCI value for the route processor leg, select a VCI value higher than 300 to prevent a conflict with an automatically assigned VCI for well-known channels if the ATM switch router reboots.

Displaying the Terminating PVC Connections

To display the terminating PVC configuration VCs on the interface, use the following EXEC command:

See Displaying VCCs for examples of the show atm vc commands.

Configuring PVP Connections

This section describes configuring a permanent virtual path (PVP) connection. Figure 6-3 shows an example of PVPs configured through the ATM switch routers.

To configure a PVP connection, perform the following steps, beginning in global configuration mode:

Note   When configuring PVP connections, begin with lower virtual path identifier (VPI) numbers. Using low VPI numbers allows more efficient use of the switch fabric resources.

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Note   This parameter specifies the weight assigned to the output VC for weighted round robin scheduling and is an integer in the range of 1 to 15.This parameter is valid only on systems equipped with the switch processor feature card. (Catalyst 8540 MSR and Catalyst 8510 MSR and LightStream 1010 with FC-PFQ). For more information on scheduling, see "Scheduling Output" in the Guide to ATM Technology.

Note   The sched option is only available on OC-48c interfaces. Each OC-48c interface has four OC-12 schedulers. The sched variable is used to select the specific OC-12 scheduler for which the virtual circuit is assigned for output on an interface and is therefore a number between 1 and 4.

Examples

The following example shows how to configure the internal cross-connect PVP within Switch B between interfaces 4/0/0, VPI = 30, and interface ATM 1/1/1, VPI = 45:

The following example shows how to configure the internal cross-connect PVP within Switch C between interfaces 0/1/3, VPI = 45, and interface ATM 1/1/0, VPI = 50:

Each subsequent PVP cross connection and link must be configured until the VP is terminated to create the entire PVP.

Displaying PVP Configuration

To show the ATM interface configuration, use the following EXEC command:

Example

The following example shows the PVP configuration of Switch B:

The following example shows the PVP configuration of Switch B with the switch processor feature card installed:

Deleting PVPs from an Interface

This section describes how to delete a PVP configured on an interface. To delete a PVP, perform the following steps, beginning in global configuration mode:

Example

The following example shows how to delete the PVP on ATM interface 1/1/0, VPI = 200:

Confirming PVP Deletion

To confirm the deletion of a PVP from an interface, use the following EXEC command before and after deleting the PVP:

Example

The following example shows how to confirm that the PVP is deleted from the interface:

Configuring Point-to-Multipoint PVC Connections

This section describes configuring point-to-multipoint PVC connections. In Figure 6-4, cells entering the ATM switch router at the root point (on the left side at interface ATM 0/0/0, VPI = 50, VCI = 100) are duplicated and switched to the leaf points (output interfaces) on the right side of the figure.

Note   If desired, one of the leaf points can terminate in the ATM switch router at the route processor interface ATM 0.

To configure the point-to-multipoint PVC connections shown in Figure 6-4, perform the following steps, beginning in global configuration mode:

To configure the point-to-multipoint PVC connections using the atm pvc command, the root point is port A and the leaf points are port B.

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Note   This parameter specifies the weight assigned to the output VC for weighted round robin scheduling and is an integer in the range of 1 to 15.This parameter is valid only on systems equipped with the switch processor feature card. (Catalyst 8540 MSR and Catalyst 8510 MSR and LightStream 1010 with FC-PFQ). For more information on scheduling, see "Scheduling Output" in the Guide to ATM Technology.

Note   The sched option is only available on OC-48c interfaces. Each OC-48c interface has four OC-12 schedulers. The sched variable is used to select the specific OC-12 scheduler for which the virtual circuit is assigned for output on an interface and is therefore a number between 1 and 4.

Examples

The following example shows how to configure the root-point PVC on ATM switch router interface ATM 0/0/0, VPI = 50, VCI = 100, to the leaf-point interfaces (see Figure 6-4):

Displaying Point-to-Multipoint PVC Configuration

To display the point-to-multipoint PVC configuration, use the following EXEC mode command:

Examples

The following example shows the PVC configuration of the point-to-multipoint connections on ATM interface 0/0/0:

The following example shows the VC configuration on interface ATM 0/0/0, VPI = 50, VCI = 100, with the switch processor feature card installed:

Configuring Point-to-Multipoint PVP Connections

This section describes configuring point-to-multipoint PVP connections. Figure 6-5 provides an example of point-to-multipoint PVP connections.

In Figure 6-5, cells entering the ATM switch router at the root point (the left side at interface ATM 4/0/0), VPI = 50, are duplicated and switched to the leaf points (output interfaces), on the right side of the figure.

To configure point-to-multipoint PVP connections, perform the following steps, beginning in global configuration mode:

To configure the point-to-multipoint PVP connections using the atm pvp command, the root point is port A and the leaf points are port B.

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Examples

The following example shows how to configure the root-point PVP on ATM switch router interface ATM 4/0/0 (VPI = 50), to the leaf point interfaces ATM 1/1/1 (VPI = 60), ATM 3/0/0 (VPI = 70), and ATM 3/0/3 (VPI = 80) (see Figure 6-5):

Displaying Point-to-Multipoint PVP Configuration

To display the ATM interface configuration, use the following EXEC command:

Examples

The following example shows the PVP configuration of the point-to-multipoint PVP connections on ATM interface 4/0/0:

The following example shows the PVP configuration of the point-to-multipoint PVP connections on ATM interface 4/0/0, VPI = 50, with the switch processor feature card installed:

Configuring Soft PVC Connections

This section describes configuring soft permanent virtual channel (PVC) connections, which provide the following features:

Figure 6-6 illustrates the soft PVC connections used in the following examples.

Guidelines for Creating Soft PVCs

Perform the following steps when you configure soft PVCs:

Step 2   Decide which of these two ports you want to designate as the destination (or passive) side of the soft PVC.

This decision is arbitrary—it makes no difference which port you define as the destination end of the circuit.

Step 3   Retrieve the ATM address of the destination end of the soft PVC using the show atm address command.

Step 4   Retrieve the VPI/VCI values for the circuit using the show atm vc command.

Step 5   Configure the source (active) end of the soft PVC. At the same time, complete the soft PVC setup using the information derived from Step 3 and Step 4. Be sure to select an unused VPI/VCI value (one that does not appear in the show atm vc display).

Note   To ensure that the soft PVCs are preserved during a route processor switchover, you must configure the switch to synchronize dynamic information between the route processors. For more information, see "Initially Configuring the ATM Switch Router."

Configuring Soft PVCs

To configure a soft PVC connection, perform the following steps, beginning in privileged EXEC mode:

Note   The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See "Configuring Resource Management."

Examples

The following example shows the destination ATM address of the interface connected to User D:

The following example shows how to configure a soft PVC on Switch B between interface ATM 0/0/2, source VPI = 0, VCI = 1000; and Switch C, destination VPI = 0, VCI = 1000 with a specified ATM address (see Figure 6-6):

Displaying Soft PVC Configuration

To display the soft PVC configuration at either end of a ATM switch router, use the following EXEC commands:

Examples

The following example shows the soft PVC configuration of Switch B, on interface ATM 0/0/2 out to the ATM network:

The following example shows the soft PVC configuration of Switch C, on interface ATM 1/1/1 out to the ATM network:

The following example shows the soft PVC configuration of Switch B, on interface ATM 0/0/2 (VPI = 0, VCI = 1000) out to the ATM network with the switch processor feature card installed:

Configuring Soft PVP Connections

This section describes configuring soft permanent virtual path (PVP) connections, which provide the following features:

Figure 6-7 is an illustration of the soft PVP connections used in the examples in this section.

To configure a soft PVP connection, perform the following steps, beginning in global configuration mode:

The row index for rx-cttr and tx-cttr must be configured before using this optional parameter. See the "Configuring Resource Management.".

Example

The following example shows how to configure a soft PVP on Switch B between interface ATM 0/0/2, source VPI = 75; and Switch C, destination VPI = 75, with a specified ATM address (see Figure 6-7):

Displaying Soft PVP Connections

To display the ATM soft PVP configuration, use the following EXEC command:

Examples

The following example shows the soft PVP configuration at Switch B, on interface ATM 0/0/2 out to the ATM network:

The following example shows the soft PVP configuration on interface ATM 1/1/1 at Switch C out to the ATM network:

The following example shows the soft PVP configuration at Switch B on interface ATM 0/0/2 (VPI = 75) out to the ATM network with the switch processor feature card installed:

Configuring the Soft PVP or Soft PVC Route Optimization Feature

This section describes the soft PVP or soft PVC route optimization feature. Most soft PVPs or soft PVCs have a much longer lifetime than SVCs. The route chosen during the soft connection setup remains the same even though the network topology might change.

Soft connections, with the route optimization percentage threshold set, provide the following features:

Route optimization is directly related to administrative weight, which is similar to hop count. For a description of administrative weight, see "Configuring ATM Routing and PNNI."

Configuring soft PVP or soft PVC route optimization is described in the following sections:

For overview information about the route optimization feature refer to the Guide to ATM Technology.

Enabling Soft PVP or Soft PVC Route Optimization

Soft PVP or soft PVC route optimization must be enabled and a threshold level configured to determine the point when a better route is identified and the old route is reconfigured.

To enable and configure route optimization, use the following global configuration command:

Example

The following example enables route optimization and sets the threshold percentage to 85 percent:

Configuring a Soft PVP/PVC Interface with Route Optimization

Soft PVP or soft PVC route optimization must be enabled and configured to determine the point at which a better route is found and the old route is reconfigured.

To enable and configure a soft PVC/PVP interface with route optimization, perform the following steps, beginning in global configuration mode:

Example

The following example shows how to configure an interface with a route optimization interval configured as every 30 minutes between the hours of 6:00 P.M. and 5:00 A.M.:

Displaying an Interface Route Optimization Configuration

To display the interface route optimization configuration, use the following EXEC command:

Example

The following example shows the route optimization configuration of ATM interface 0/0/0:

Configuring Soft PVCs with Explicit Paths

Normally, soft PVCs and soft PVPs are automatically routed by PNNI over paths that meet the traffic parameter objectives. However, for cases where manually configured paths are needed, PNNI explicit paths can optionally be specified for routing the soft PVC or soft PVP. For detailed information on configuring PNNI explicit paths, see "Configuring ATM Routing and PNNI."

The explicit paths are assigned using precedence numbers 1 through 3. The precedence 1 path is tried first and if it fails the soft connection is routed using the precedence 2 path and so forth. If all of the explicit paths fail, standard on-demand PNNI routing is tried unless the only-explicit keyword is specified.

If the soft connection destination address is reachable at one of the included entries in an explicit path, any following entries in that path are automatically disregarded. This allows longer paths to be reused for closer destinations. Alternatively, the upto keyword can be specified for an explicit path in order to disregard later path entries.

Example

The following example shows how to configure a soft PVC between ATM switch router dallas_1 and an address on ATM switch router new_york_3 using either of the two explicit paths new_york.path1 and new_york.path2. If both explicit paths fail, the ATM switch router uses PNNI on-demand routing to calculate the route.

Changing Explicit Paths for an Existing Soft PVC

Explicit paths can be added, modified or removed without tearing down existing soft PVCs by using the redo-explicit keyword. Only the source VPI and VCI options need to be specified. All applicable explicit path options are replaced by the respecified explicit path options.

The soft PVC is not immediately rerouted using the new explicit path. However, reroutes using the new explicit path can happen for the following four reasons:

1. A failure occurs along the current path.

2. The EXEC command atm route-optimization soft-connection is entered for the soft PVC.

3. route-optimization is enabled and the retry time interval has expired.

4. The soft PVC is disabled and then reenabled using the disable and enable keywords.

Example

The following example shows how to change the explicit path configuration for an existing soft PVC on the ATM switch router dallas_1 without tearing down the connection. The new configuration specifies the two explicit paths, new_york.path3 and new_york.path4, and uses the only-explicit option.

Note   The configuration displayed for soft connections with explicit paths is always shown as two separate lines using the redo-explicit keyword on the second line, even if it is originally configured using a single command line.

Displaying Explicit Path for Soft PVC Connections

To display a soft PVC connection successfully routed over an explicit path, use the following EXEC command:

Example

The following example shows the last explicit path status for a soft PVC using the show atm vc interface EXEC command. Note that the first listed explicit path new_york.path2 shows an unreachable result, but the second explicit path new_york.path1 succeeded.

Configuring Soft PVCs and Soft PVPs with Priority

This section describes how to specify priority for soft PVCs or PVPs established over an Inverse Mulitplexing for ATM (IMA) interface. If an IMA link goes down, the performance of all virtual connections requesting guaranteed bandwidth (CBR, VBR-RT/NRT, ABR/UBR+ with nonzero MCR) can be adversely affected. By configuring the priority for soft PVCs or PVPs, connections with the highest priority are more likely to be preserved if an IMA link goes down, while connections with lower or no priorities are cleared, thereby maintaining bandwidth for the most important connections. A priority of 0 (highest) to 15 (lowest) can be specified for each soft PVC.

Note   Connections of the highest priority may be randomly chosen for clearing if insufficient bandwidth is available.

If an IMA link goes down, a check is made to see whether the reduced interface bandwidth is greater than that allocated to connections. If the available bandwidth is below that allocated, the qualifying signaled VCs are checked to see if they have allocated guaranteed bandwidth. If signaled VCs have allocated guaranteed bandwidth, they are released on a priority basis until either the bandwidth allocated is less than that available, or there are no guaranteed-bandwidth signaled VCs.

Note   A signaled VC must have allocated bandwidth in order to be released by priority. Therefore, simple UBR VCs cannot be released by priority. UBR+ VCs, however, have allocated bandwidth and can therefore be released by priority.

Note   Though unaffected by priority configuration, the bandwidth allocated by PVCs is considered when determining whether or not the bandwidth allocated is below that available.

To specify that soft PVCs can be cleared by priority, perform the following task on an IMA interface:

Configuring a Soft PVC with priority

To configure a soft PVC with priority, perform the following steps:

Note   If not priority is specified, the soft PVC is assigned a priority of 15 (lowest).

Note   If the atm svc-clear by-priority command is not enabled, none of the hold-priority configurations are considered when bandwidth is dropped on an interface.

Configuring a Soft PVP with Priority

To configure a soft PVP with priority, perform the following steps:

Configuring a Soft PVC with Priority for a CES Circuit

To configure a soft PVC with priority for a circuit emulation service (CES) circuit, use the following command:

Configuring a Soft PVC with Priority for Frame Relay Connections

To configure a soft PVC with priority between a Frame Relay connection and an ATM connection, use the following command:

To configure a soft PVC with priority between two Frame Relay connections, use the following command:

To display a soft PVC with priority, use the following command:

Example

The following example shows the configuration of a soft PVC with priority on an IMA interface.

Configuring Two-Ended Soft PVC and Soft PVP Connections

With two-ended soft PVC provisioning, you can configure a passive half leg on the terminating switch of a soft PVC. This allows resources on the terminating switch to be reserved for the incoming soft PVC. Also, the UPC option can be configured for an individual soft PVC allowing traffic policing.

You can configure the passive half-leg (using the two-ended soft PVC feature) with the following parameters:

The passive leg is used provided the traffic parameters of the leg match with the incoming connection setup request and the leg is in a "Not Connected" state. If the passive leg is not pre-configured, the default values are used when creating the dynamic leg.

Figure 6-8 shows a soft PVC between ATM switch routers and PVCs configured on both ends connecting the routers. In this example the passive half-leg is configured at the destination end at ATM switch router C.

Configuring Two-Ended Soft PVC Connections

To configure a two-ended soft PVC connection, follow these steps:

.

Note   The default value for the upc option is pass.

Note   The default value for the pd option is off.

Note   For VBR-nrt and VBR-rt service categories you must configure the MBS (even if the value is default) in the ATM connection traffic table row attached to the passive leg.

Note   You can use the debug atm sig-soft (interface) and debug atm rm events commands to get information on why a passive leg is not used due to traffic parameter mismatches.

Configuring Two-Ended Soft PVP Connections

To configure a two-ended soft PVP connection, follow these steps:

.

Note   The default value for the upc option is pass.

Note   For VBR-nrt and VBR-rt service categories you must configure the MBS (even if the value is default) in the ATM connection traffic table row attached to the passive leg.

Note   You can use the debug atm sig-soft (interface) and debug atm rm events commands to get information on why a passive leg is not used due to traffic parameter mismatches.

Examples

The following example shows the configuration of the two-ended soft PVC (shown in Figure 6-8) with a passive half leg starting with the configuration of Switch-C.

On Switch-B, create a two-ended soft PVC on the source switch that uses the passive half leg on the terminating switch.

On Switch-C, display the passive half-leg configuration information of two-ended soft PVC.

The following example shows the configuration of the two-ended soft PVP with a passive half leg starting with the configuration of Switch-C.

On Switch-B, create a two-ended soft PVP on the source switch that uses the passive half leg on the terminating switch.

On Switch-C, display the passive half-leg configuration information of two-ended soft PVP.

Configuring Nondefault Well-Known PVCs

Normally the default well-known VCs are automatically created with default virtual channel identifiers (VCIs). However, for the unusual instances where the ATM switch router interfaces with nonstandard equipment, you can configure nondefault well-known VCI values on a per-interface basis.

For overview information about the well-known PVCs, refer to the Guide to ATM Technology.

Table 6-2 lists the default well-known VCs and their default configuration.

Caution   Do not change the well-known channels to use a VC where the remote end is sending AAL5 messages not intended for the well-known VC. For example, do not swap VC values between two types of well-known VCs.

When you configure well-known VCs on physical interfaces using the CBR service category, the VC scheduling on the external interface is the same as the CBR VC configuration. This means that the VCs are allocated the bandwidth specified and are limited to that same bandwidth (shaped).

Note   The connection from an external interface to the route processor is never shaped.

Overview of Nondefault PVC Configuration

Following is an overview of the steps needed to configure nondefault well-known VCs:

Step 2   Delete any existing automatically created well-known VCs.

Step 3   Configure the individual encapsulation type as follows:

Step 4   Copy the running-configuration file to the startup-configuration file.

Configuring Nondefault PVCs

To configure the nondefault PVCs for signalling, ILMI, and PNNI, perform the following steps, beginning in global configuration mode:

Note   An error condition occurs if either the signalling or ILMI well-known VCs remain unconfigured when an interface is enabled.

When you configure well-known VCs on physical interfaces using the CBR service category, the VC scheduling on the external interface is the same as the CBR VC configuration. This means that the VCs are allocated the bandwidth specified and are limited to that same bandwidth (shaped).

Note   The connection from an external interface to the route processor is never shaped.

Example

The following example shows the nondefault VC configuration steps:

Step 2   Change to interface configuration mode for ATM interface 0/0/0.

Step 3   Enter manual well-known-vc mode and delete the existing default well-known VCs using the atm manual-well-known-vc delete command.

Step 4   Confirm deletion by entering y.

Step 5   Configure the nondefault VC for signalling from 5 (the default) to 35 using the atm pvc command.

Step 6   Configure the ILMI VC, then configure the PNNI VC if needed using the same procedure.

Step 7   Save the new running configuration to the startup configuration.

An example of this procedure follows:

Configuring a VPI/VCI Range for SVPs and SVCs

You can configure a virtual path identifier/virtual channel identifier (VPI/VCI) range for switched virtual channels and switched virtual paths (SVCs and SVPs). ILMI uses the specified range to negotiate the VPI/VCI range parameters with peers. This feature allows you to:

You can still configure PVPs and PVCs in any supported range, including any VPI/VCI range you configured for SVPs/SVCs.

Note   This feature is supported in ILMI 4.0.

Note   To ensure that SVCs are preserved during a route processor switchover, you must configure the switch to synchronize dynamic information between the route processors. For more information, see "Initially Configuring the ATM Switch Router."

The default maximum switched virtual path connection (SVPC) VPI is equal to 255. You can change the maximum SVPC VPI by entering the atm svpc vpi max value command. See Table 6-3 for the allowable ranges.

Note   The maximum value specified applies to all interfaces except logical interfaces, which have a fixed value of 0.

For further information and examples of using VPI/VCI ranges for SVPs/SVCs, refer to the Guide to ATM Technology.

Every interface negotiates the local values for the maximum SVPC VPI, maximum SVCC VPI, and minimum SVCC VCI with the peer's local value during ILMI initialization. The negotiated values determine the ranges for SVPs and SVCs. If the peer interface does not support these objects or autoconfiguration is turned off on the local interface, the local values determine the range.

To configure a VPI/VCI range for SVCs/SVPs, perform the following steps, beginning in global configuration mode:

The following example shows configuring ATM interface 0/0/0 with the SVPC and SVCC VPI maximum set to 100, and SVCC VCI minimum set to 60.

Displaying the VPI/VCI Range Configuration

To confirm the VPI or VCI range configuration, use one of the following commands:

Examples

The following example shows how to confirm the VPI and VCI range configuration on an ATM interface. The values displayed for ConfMaxSvpcVpi, ConfMaxSvccVpi, and ConfMinSvccVci are local values. The values displayed for CurrMaxSvpcVpi, CurrMaxSvccVpi, and CurrMinSvccVci are negotiated values.

The following example shows how to confirm the peer's local values for VPI and VCI range configuration by displaying the ILMI status on an ATM interface:

Note   Note that the show atm ilmi-status command displays the information above only if the peer supports it.

Configuring VP Tunnels

This section describes configuring virtual path (VP) tunnels, which provide the ability to interconnect ATM switch routers across public networks using PVPs. You can configure a VP tunnel to carry a single service category, or you can configure a VP tunnel to carry multiple service categories, including merged VCs.

Figure 6-9 shows a public UNI interface over a DS3 connection between the ATM switch router (HB-1) in the Headquarters building and the ATM switch router (SB-1) in the Remote Sales building. To support signalling across this connection, a VP tunnel must be configured.

Configuring a VP Tunnel for a Single Service Category

The type of VP tunnel described in this section is configured as a VP of a single service category. Only virtual circuits (VCs) of that service category can transit the tunnel.

To configure a VP tunnel connection for a single service category, perform the following steps, beginning in global configuration mode:

Note   The row index for nondefault rx-cttr and tx-cttr must be configured before these optional parameters are used.

Examples

The following example shows how to configure the ATM VP tunnel on the ATM switch router (HB-1) at interface ATM 1/0/0, VPI 99:

The following example shows how to configure the ATM VP tunnel on the ATM switch router (SB-1) interface ATM 0/0/0, VPI 99:

Displaying the VP Tunnel Configuration

To show the ATM virtual interface configuration, use the following EXEC command:

The following example shows the ATM virtual interface configuration for interface ATM 1/0/0.99:

Configuring a Shaped VP Tunnel

This section describes configuring a shaped VP tunnel for a single service category with rate-limited tunnel output on a switch.

A shaped VP tunnel is configured as a VP of the CBR service category. By default, this tunnel can carry VCs only of the CBR service category. However, you can configure this VP tunnel to carry VCs of other service categories. The overall output of this VP tunnel is rate-limited by hardware to the peak cell rate (PCR) of the tunnel.

Note   Shaped VP tunnels are supported only on systems with the FC-PFQ feature card. (Catalyst 8510 MSR and LightStream 1010)

A shaped VP tunnel is defined as a CBR VP with a PCR. The following limitations apply:

Configuring a Shaped VP Tunnel on an Interface

To configure a shaped VP tunnel, perform the following steps, beginning in global configuration mode:

Note   The rx-cttr and tx-cttr row indexes must be configured before they are used.

Example

The following example shows how to configure a shaped VP tunnel with a VPI of 99 as ATM interface 0/0/0.99

Displaying the Shaped VP Tunnel Configuration

To display the shaped VP tunnel interface configuration, use the following EXEC command:

For an example display from the show atm interface command, see Displaying the Hierarchical VP Tunnel Configuration.

Configuring a Hierarchical VP Tunnel for Multiple Service Categories

This section describes configuring a hierarchical VP tunnel for multiple service categories with rate-limited tunnel output.

A hierarchical VP tunnel allows VCs of multiple service categories to pass through the tunnel. In addition, the overall output of the VP tunnel is rate-limited to the PCR of the tunnel. There is no general limit on the number of connections allowed on a such a tunnel. Hierarchical VP tunnels can also support merged VCs for tag switching. See "Configuring Tag Switching and MPLS."

Service categories supported include the following:

While capable of carrying any traffic category, a hierarchical VP tunnel is itself defined as CBR with a PCR. The following limitations apply on the Catalyst 8540 MSR:

The following limitations apply on the Catalyst 8510 MSR and LightStream 1010:

The following limitations apply on the Catalyst 8540 MSR, Catalyst 8510 MSR and LightStream 1010:

Enabling Hierarchical Mode

Before configuring a hierarchical VP tunnel, you must first enable hierarchical mode, then reload the ATM switch router. Perform the following steps, beginning in global configuration mode:

Note   Enabling hierarchical mode causes the minimum rate allocated for guaranteed bandwidth to a connection to be increased.

Example

The following example shows how to enable hierarchical mode, then save and reload the configuration.

Configuring a Hierarchical VP Tunnel on an Interface

To configure a hierarchical VP tunnel, perform the following steps, beginning in global configuration mode:

Note   The rx-cttr and tx-cttr row indexes must be configured before they are used.

Example

The following example shows how to configure a hierarchical VP tunnel with a PVP of 99 as ATM interface 0/0/0.99

Displaying the Hierarchical VP Tunnel Configuration

To display the hierarchical VP tunnel interface configuration, use the following EXEC command:

Example

The following example shows the VP tunnel configuration on interface ATM 1/0/0 with PVP 99: