Configuring Individual ATM PVC Parameters

As an alternative to using the atm pvc command to configure ATM PVC parameters with a single command, you can access ATM VC Configuration mode to configure individual ATM PVC parameters with separate commands, one parameter at a time. You can configure parameters for the service category, encapsulation method, F5 OAM options, and Inverse ARP.

The following sections explain the benefits of using ATM VC Configuration mode and describes how to configure the ATM VC mode :

• Benefits
• Creating Control PVCs
• Creating Data PVCs
• Configuring the Service Category for Data PVCs
• Configuring Encapsulation for Data PVCs
• Configuring F5 OAM for Data PVCs
• Configuring Inverse ARP for Data PVCs

Benefits

Using commands in ATM VC Configuration mode to configure individual ATM PVC parameters provides the following benefits:

• Commands in ATM VC Configuration mode are less complex and easier to use.

  With the atm pvc command and keywords, you configure multiple PVC attributes on a single command line. In addition, configuration attributes available only for control (ILMI and signaling) PVCs or only for data PVCs are not mutually exclusive.

  By contrast, ATM VC Configuration mode provides commands to configure each parameter individually, and makes a clearer distinction between configuration of control PVCs and configuration of data PVCs.

• ATM VC Configuration mode interoperates with the atm pvc command.

  You can configure all of the parameters currently supported by the atm pvc command from within ATM VC Configuration mode. In addition, you can create a PVC with the atm pvc command and modify or delete the same PVC by using ATM VC Configuration mode. Conversely, you can modify (with certain restrictions) or delete a PVC created in ATM VC Configuration mode by using the atm pvc command.

• ATM VC Configuration mode supports additional F5 OAM alarm surveillance and VC integrity options.

  In most cases, you can use either an ATM VC Configuration mode command or the atm pvc command to configure ATM PVC parameters. However, to configure F5 OAM alarm surveillance parameters (by using the oam ais-rdi command) or VC integrity parameters (by using the oam retry command), you must use only ATM VC Configuration mode. There are no equivalent atm pvc commands to configure these parameters.

  You can, however, continue to use the atm pvc command to enable VC integrity and modify the loopback frequency of an ATM data PVC.

  Note: If you have existing configuration scripts that use the atm pvc command, we recommend that you continue to use the atm pvc command to configure all ATM PVC parameters except those that require you to use the oam ais-rdi command or oam retry command in ATM VC Configuration mode.

Creating Control PVCs

A control PVC, also referred to as a control circuit, supports services such as ILMI to manage and control ATM networks. You must create a control PVC on an ATM major interface, and not on an ATM 1483 subinterface that is stacked above an ATM major interface.

To create a control PVC, you issue the pvc command from Interface Configuration mode. However, unlike the other tasks in this section, configuring a control PVC with the pvc command does not access ATM VC Configuration mode.

For example, the following commands create a control PVC with VCD 10, VPI 0, VCI 16, and ILMI encapsulation.

Regardless of whether you use the pvc command or the atm pvc command to create a control PVC, you cannot modify the VCD, VPI, or VCI values after they have been configured.

pvc

• Use from Interface Configuration mode to create a control PVC for Integrated Local Management Interface (ILMI).
• To create a control PVC, specify the VCD, VPI and VCI (in the format vpi/vci), and the ilmi keyword.
• Example

  host1(config-if)#pvc 5 0/5 ilmi

• Use the no version to remove the specified control PVC from the router.
• See pvc.

Creating Data PVCs

A data PVC, also referred to as a data circuit, is an ATM PVC that carries data. You must create a data PVC on an ATM 1483 subinterface that is stacked above an ATM major interface, and not on the ATM major interface itself.

To create a data PVC, you issue the pvc command from Subinterface Configuration mode to access ATM VC Configuration mode. From ATM VC Configuration mode, you can then do either of the following:

• Issue the exit command, which creates a data PVC that uses default values for service category (unspecified bit rate without a peak cell rate), encapsulation type (aal5snap), F5 OAM (disabled), and Inverse ARP (disabled).
• Issue commands to configure or modify data PVC attributes including the service category, encapsulation type, F5 OAM, and Inverse ARP.

For example, the following commands create a data PVC with VCD 32, VPI 0, VCI 100 and default values for the other attributes. Issuing the exit command causes the configuration to take effect.

Regardless of whether you use the pvc command or the atm pvc command to create a data PVC, you cannot modify the VCD, VPI, or VCI values after they have been configured.

pvc

• Use from Subinterface Configuration mode to create a data PVC and access ATM VC Configuration mode, from which you can configure and modify individual PVC attributes one at a time.
• To create a basic data PVC with default values for service category, encapsulation type, F5 OAM, and Inverse ARP, specify the VCD and the VPI and VCI (in the format vpi/vci).
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif)#pvc 10 15/50

  host1(config-subif-atm-vc)#exit

• Use the no version to remove the specified data PVC from the router.
• See pvc.

Configuring the Service Category for Data PVCs

You can use individual commands in ATM VC Configuration mode to configure each supported service category on a data PVC, or to restore the default service category, unspecified bit rate (UBR) without a peak cell rate (PCR).

For example, the following commands configure a data PVC that uses the constant bit rate (CBR) service category with a nondefault PCR (10,000 Kbps). Issuing the exit command causes the configuration to take effect.

cbr

• Use to configure the CBR service category on an ATM data PVC.
• You must specify a PCR, in Kbps, in the range 1–149760 (for OC3 ATM modules) or 1–599040 (for OC12 ATM modules).
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#cbr 15000

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default service category, UBR without a PCR.
• See cbr.

ubr

• Use to configure the UBR service category on an ATM data PVC.
• You can optionally specify a PCR, in Kbps, in the range 0–149760 (for OC3 ATM modules) or 0–599040 (for OC12 ATM modules).
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#ubr 5000

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default service category, UBR without a PCR.
• See ubr.

vbr-nrt

• Use to configure the variable bit rate, nonreal time (VBR-NRT) service category on an ATM data PVC.
• You must specify all of the following parameters:
  • PCR, in Kbps, in the range 0–149760 (for OC3 ATM modules) or 0–599040 (for OC12 ATM modules)
  • SCR, in Kbps, in the range 0–149760 (for OC3 ATM modules) or 0–599040 (for OC12 ATM modules)
  • Maximum burst size (MBS), in cells, in the range 0–16777215
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#vbr-nrt 50000 10000 150

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default service category, UBR without a PCR.
• See vbr-nrt.

vbr-rt

• Use to configure the variable bit rate, real time (VBR-RT) service category on an ATM data PVC.
• You must specify all of the following parameters:
  • PCR, in Kbps, in the range 0–149760 (for OC3 ATM modules) or 0–599040 (for OC12 ATM modules)
  • SCR, in Kbps, in the range 0–149760 (for OC3 ATM modules) or 0–599040 (for OC12 ATM modules)
  • Maximum burst size (MBS), in cells, in the range 0–16777215
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#vbr-rt 200000 30000 400

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default service category, UBR without a PCR.
• See vbr-rt.

Configuring Encapsulation for Data PVCs

The encapsulation method on a data PVC represents the format of the data units that traverse the circuit. You can use the encapsulation command in ATM VC Configuration mode to configure the encapsulation method for a data PVC, or to restore the default encapsulation method, aal5snap.

For example, the following commands configure a data PVC that uses aal5all encapsulation. Issuing the exit command causes the configuration to take effect.

encapsulation

• Use to configure the encapsulation method on an ATM data PVC.
• Specify one of the following encapsulation types:
  • aal0—Causes the router to receive raw ATM cells on this PVC and forward the cells without performing AAL5 packet reassembly
  • aal5all—Configures ATM over MPLS passthrough connections; the router passes through all ATM AAL5 traffic without interpreting it
  • aal5autoconfig—Enables autodetection of the 1483 encapsulation (LLC/SNAP or VC multiplexed)
  • aal5mux ip—Configures a VC-based multiplexed circuit used for IP only
  • aal5snap—Configures an LLC encapsulated circuit; an LLC/SNAP header precedes the protocol datagram; this is the default encapsulation method
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#encapsulation aal5mux ip

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default encapsulation method, aal5snap.
• See encapsulation.

Configuring F5 OAM for Data PVCs

In ATM VC Configuration mode, you can use the individual commands listed in Table 7 to configure nondefault values for F5 OAM services.

Table 7: F5 OAM Configuration Tasks and Associated Commands

For more information about OAM parameters, see Operations, Administration, and Management of ATM Interfaces .

Note: The oam-ais rdi command and the oam retry command are available only in ATM VC Configuration mode. There is no equivalent atm pvc command to configure these F5 OAM alarm surveillance and VC integrity parameters.

For example, the following commands enable VC integrity on a data PVC with a nondefault loopback frequency (30 seconds). Issuing the exit command causes the configuration to take effect.

The following commands, which are available only in ATM VC Configuration mode, configure nondefault VC integrity and alarm surveillance parameters on a data PVC. In this example, the VC integrity parameters configured with the oam retry command include the up retry count (4), down retry count (6), and retry frequency (2). The alarm surveillance parameters configured with the oam ais-rdi command include the alarm down count (2) and alarm clear timeout duration (4 seconds). Issuing the exit command causes the configuration to take effect.

oam ais-rdi

• Use to configure surveillance parameters for AIS and RDI F5 OAM fault management cells on an ATM data PVC.
• You can optionally specify the following values:
  • alarmDownCount—Number of successive alarm cells, in the range 1–60, for the router to receive before reporting that a PVC is down; the default value is 1
  • alarmClearTimeout—Number of seconds, in the range 3–60, for the router to wait before reporting that a PVC is up after the PVC has stopped receiving alarm cells; the default value is 3
• To configure these alarm surveillance parameters, you must use the oam ais-rdi command in ATM VC Configuration mode. There is no equivalent atm pvc command to configure these parameters.
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#oam ais-rdi 5 10

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default values for the alarm down count and alarm clear timeout duration.
• See oam ais-rdi.

oam cc

• Use to enable F5 OAM CC verification on an ATM data PVC.
• You can optionally specify one of the following values to configure CC cell flows:
  • segment—Opens an F5 OAM CC segment cell flow
  • end-to-end—Opens an F5 OAM CC end-to-end cell flow
• You must specify one of the following values to enable CC verification:
  • source—Enables this VC as the source point (cell generator)
  • sink—Enables this VC as a sink point (cell receiver)
  • both—Enables this VC as both a sink point and a source point
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example 1—Enables CC verification with a source endpoint

  host1(config-subif-atm-vc)#oam cc source

  host1(config-subif-atm-vc)#exit

• Example 2—Opens an F5 OAM CC segment cell flow and enables CC verification with a sink endpoint

  host1(config-subif-atm-vc)#oam cc segment sink

  host1(config-subif-atm-vc)#exit

• Use the no version to disable F5 OAM CC verification and restore the default setting for cell termination, end-to-end.
• See oam cc.

oam-pvc

• Use to enable generation of F5 OAM loopback cells on an ATM data PVC and, optionally, enable F5 OAM VC integrity features on the circuit.
• Use this command only on data PVCs configured with aal5snap, aal5autoconfig, or aal5 mux ip encapsulation; the command is not valid for data PVCs configured with other encapsulation types.
• To enable F5 OAM VC integrity on the PVC, use the manage keyword.
• You can optionally specify the number of seconds, in the range 1–600, for the router to wait between the transmission of loopback cells during normal operation; the default value is 10.
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#oam-pvc manage 15

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default behavior, which disables F5 OAM VC integrity on the router and restores the default value for loopback frequency, 10 seconds.
• See oam-pvc/

oam retry

• Use to configure F5 OAM VC integrity parameters on an ATM data PVC.
• You can optionally specify the following values:
  • upRetryCount—Number of successive loopback cell responses, in the range 1–60, for the router to receive before reporting that a PVC is up; default value is 3
  • downRetryCount—Number of successive loopback cell responses, in the range 1–60, for the router to miss before reporting that a PVC is down; default value is 5
  • retryFrequency—Number of seconds, in the range 1–600, for the router to wait between the transmission of loopback cells when it is verifying the state of the PVC; default value is 1
• To configure these VC integrity parameters, you must use the oam retry command in ATM VC Configuration mode. There is no equivalent atm pvc command to configure these parameters.
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#oam retry 5 6 3

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default values for the up retry count, down retry count, and retry frequency parameters.
• See oam retry.

Configuring Inverse ARP for Data PVCs

You can use the inarp command in ATM VC Configuration mode to enable Inverse ARP (InARP) on a data PVC that resides on an ATM 1483 NBMA subinterface configured with the multipoint option. The PVC must use the default encapsulation method, aal5snap. For more information about InARP, see Configuring an NBMA Interface.

For example, the following commands enable InARP with a nondefault refresh rate (10 minutes) on a data PVC. The PVC uses aal5snap encapsulation by default. Issuing the exit command causes the configuration to take effect.

inarp

• Use to enable Inverse ARP on an ATM PVC that resides on an ATM 1483 NBMA subinterface and uses the default encapsulation method, aal5snap.
• You can optionally specify an Inverse ARP refresh rate, in the range 1–60 minutes; the default value is 15.
• You must issue the exit command from ATM VC Configuration mode for the configuration to take effect.
• Example

  host1(config-subif-atm-vc)#inarp 5

  host1(config-subif-atm-vc)#exit

• Use the no version to restore the default behavior, which disables Inverse ARP on the router.
• See inarp.

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