# Setting Optional Parameters

You can also set the following parameters:

- Set the administrative state of an ATM AAL5 interface to disabled.
  host1(config-if)#atm aal5 shutdown
- Enable CAC on the interface.
  host1(config-if)#atm cac 3000000 ubr 3000
- Configure the clock source.
  host1(config-if)#atm clock internal
- Configure framing on a T3/E3 physical interface.
  host1(config-if)#atm framing g751adm
- Enable ILMI on the interface.
  host1(config-if)#atm ilmi-enable
- Set the ILMI keepalive timer.
  host1(config-if)#atm ilmi-keepalive 5
- Specify the cable length (line build-out) for the ATM interface.
  host1(config-if)#atm lbo long
- Set the administrative state of the ATM interface to disabled.
  host1(config-if)#atm shutdown
- Configure SNMP link status traps on the interface.
  host1(config-if)#atm snmp trap link-status host1(config-if)#atm aal5 snmp trap link-status
- Set the operational mode of the physical interface to SDH STM1.
  host1(config-if)#atm sonet stm-1
- Configure the UNI version of ILMI using one of the following methods:
  - Enable auto configuration of ILMI.
    host1(config-if)#atm auto-configuration
  - Set the UNI version that the router uses when ILMI link autodetermination is unsuccessful or ILMI is disabled.
    host1(config-if)#atm uni-version 4.0
- Configure the number of virtual circuits for each virtual path.
  host1(config-if)#atm vc-per-vp 128
- Configure a virtual path tunnel and its traffic parameters.
  host1(config-if)#atm vp-tunnel 2 128
- Enable scrambling of the ATM cell payload on a T3 or an E3 interface.
  host1(config-if)#ds3-scramble
- Set the time interval at which the router records bit and packet rates.
  host1(config-if)#load-interval 90
- Place the interface into loopback mode for router-to-router testing.
  host1(config-if)#loopback diagnostic
- Disable an interface.
  host1(config-if)#shutdown

## Optional Tasks on ATM 1483 Subinterfaces

You can perform the following optional tasks on ATM 1483 subinterfaces:

- Set the MTU.
  host1(config-subif)#atm atm1483 mtu 7800
- Configure SNMP link status traps.
  host1(config-subif)#atm atm1483 snmp trap link-status
- Set the administrative state of an ATM 1483 subinterface to disabled.
  host1(config-subif)#atm atm1483 shutdown
- Configure an advisory receive speed.
  host1(config-subif)#atm atm1483 advisory-rx-speed 2000

atm aal5 shutdown

- Use to set an ATM AAL5 interface administrative state to disabled.
- When you set the administrative state of the ATM AAL5 interface to disabled, the router automatically disables all F5 OAM services configured on the associated VC, and prevents the VC from receiving or transmitting F5 OAM cells.
- Example
  host1(config-if)#atm aal5 shutdown
- Use the no version to enable a disabled interface.
- See atm aal5 shutdown.

atm aal5 snmp trap link-status

- Use to enable SNMP link status traps on the AAL5 layer interface.
- Example
  host1(config-if)#atm aal5 snmp trap link-status
- Use the no version to disable the traps.
- See atm aal5 snmp trap link-status.

atm atm1483 advisory-rx-speed

- Use to set an advisory receive speed for an ATM 1483 subinterface. This setting has no effect on data forwarding. You can use it to indicate the speed of the client interface. When traffic is tunneled with L2TP, the advisory receive speed is sent from the LAC to the LNS. See LAC Configuration Prerequisites for additional information about the advisory receive speed.

  | Note: If you specify an advisory receive speed greater than 4294967 kbps, the speed is not accurately represented in the L2TP AVP, which is in bits per second (bps).

- The range is 0–2147483647 kbps.
- Example
  host1(config-subif)#atm atm1483 advisory-rx-speed 2000
- Use the no version to restore the default behavior—the RX speed is not sent to the LNS.
- See atm atm1483 advisory-rx-speed.

atm atm1483 mtu

- Use to set the MTU size for an ATM 1483 subinterface.
- The range is 256–9180.
- Example
  host1(config-subif)#atm atm1483 mtu 7800
- Use the no version to restore the default size of 9180.
- See atm atm1483 mtu.

atm atm1483 shutdown

- Use to set an ATM 1483 subinterface administrative state to disabled.
- When you set the administrative state of the ATM 1483 subinterface to disabled, the router automatically disables all F5 OAM services configured on the associated VC, and prevents the VC from receiving or transmitting F5 OAM cells.
- Example
  host1(config-subif)#atm atm1483 shutdown
- Use the no version to enable a disabled subinterface.
- See atm atm1483 shutdown.

atm atm1483 snmp trap link-status

- Use to enable SNMP link status traps on an ATM 1483 layer subinterface.
- Example
  host1(config-subif)#atm atm1483 snmp trap link-status
- Use the no version to disable the traps.
- See atm atm1483 snmp trap link-status.

atm auto-configuration

- Use to enable autoconfiguration of ILMI. Entering the atm auto-configuration command overrides any previous configuration of the atm uni-version command.
- Autoconfiguration is enabled by default.
- Example
  host1(config-if)#atm auto-configuration
- Use the no version to disable autoconfiguration and set the ILMI parameters to the UNI version configured using the atm uni-version command, which has a default value of UNI 4.0.
- See atm auto-configuration.

atm cac

- Use to enable CAC on the interface. You can set a subscription limit, so you can oversubscribe the port, and the UBR weight, so you can limit the number of UBR connections.
- You cannot configure CAC on an ATM interface on which you have created a bulk-configured VC range for use by a dynamic ATM 1483 subinterface. Conversely, you cannot create a bulk-configured VC range on an ATM interface on which you have configured CAC. For information about creating bulk-configured VC ranges, see Bulk Configuration of VC Ranges in Configuring Dynamic Interfaces Using Bulk Configuration.
- Example
  host1(config-if)#atm cac 3000000 ubr 3000
- Use the no version to disable CAC on the interface.
- See atm cac.

atm clock internal

- Use to cause the ATM interface to generate the transmit clock internally.
- You must specify one of the following:
  - module—Internal clock is from the line module (the default)
  - chassis—Internal clock is from the configured system clock
- Example
  host1(config-if)#atm clock internal
- Use the no version to cause ATM interfaces to recover the clock from the received signal.
- See atm clock internal.

atm framing

- Use to configure T3 or E3 framing on an ATM interface.
- Specify one of the following framing types for a T3 (DS3) interface:
  - cbitadm—c-bit with ATM direct mapping
  - cbitplcp—c-bit with PLCP framing (default)
  - m23adm—M23 ATM direct mapping
  - m23plcp—M23 with PLCP framing
- Specify one of the following framing types for an E3 interface:
  - g832adm—G.832 ATM direct mapping
  - g751adm—G.751 ATM direct mapping
  - g751plcp—G.751 PLCP mapping (default)
- Example
  host1(config-if)#atm framing g751adm
- Use the no version to return framing to the default:
  - For a T3 interface, the default is cbitplcp
  - For an E3 interface, the default is g751plcp
- See atm framing.

atm ilmi-enable

- Use to enable ILMI on the interface.
- Example
  host1(config-if)#atm ilmi-enable
- Use the no version to disable ILMI on the interface.
- See atm ilmi-enable.

atm ilmi-keepalive

- Use to generate ILMI keepalive messages. This value sets the time interval in seconds between poll PDU transmissions if no sequence data PDUs are pending.
- Example
  host1(config-if)#atm ilmi-keepalive 5
- Use the no version to disable the generation of keepalive messages.
- See atm ilmi-keepalive.

atm lbo

- Use to specify the cable length (line build-out) for the ATM T3 or E3 interface. The length of cable determines power requirements.
- Specify one of the following keywords:
  - long—A cable length in the range 0–225 feet
  - short—A cable length in the range 226–450 feet (the default)
- Example
  host1(config-if)#atm lbo long
- Use the no version to restore the default value, short.
- See atm lbo.

atm shutdown

- Use to set an ATM interface administrative state to disabled.
- When you set the administrative state of the ATM interface to disabled, the router automatically disables all F5 OAM services configured on the associated VC, and prevents the VC from receiving or transmitting F5 OAM cells.
- Example
  host1(config-if)#atm shutdown
- Use the no version to enable a disabled interface.
- See atm shutdown.

atm snmp trap link-status

- Use to enable SNMP link status traps on the ATM layer interface.
- Example
  host1(config-if)#atm snmp trap link-status
- Use the no version to disable the traps.
- See atm snmp trap link-status.

atm sonet stm-1

- Use to set the mode of operation on the physical interface to Synchronous Digital Hierarchy (SDH) Synchronous Transport Mode (STM).
  host1(config-if)#atm sonet stm-1
- Use the no version to restore the default value, SONET STS-3c operation.
- See atm sonet stm-1.

atm uni-version

- Use to specify the UNI version for the interface to use.
- Valid values are 3.0, 3.1, or 4.0.
- Example
  host1(config-if)#atm uni-version 4.0
- There is no no version.
- See atm uni-version.

atm vc-per-vp

- Use to configure the number of VCs for each VP. The router does not execute this command when any VCs are open on the interface.
- VCs and VP tunnels must not exist when you issue this command. If they do, you must delete the VC and VP tunnel configuration before you issue this command.
- The specified value must be a power of 2, or an error message is returned.
- The minimum number of VCs per VP is 4096 for OCx/STMx ATM line modules. If you enter a value that is below the minimum, the router uses the minimum value.
- The E120 and the E320 routers support the entire VPI/VCI range; therefore, it does not support this command.
- Example
  host1(config-if)#atm vc-per-vp 128
- Use the no version to restore the default value.
- See atm vc-per-vp.

atm vp-tunnel

- Use to define a VP tunnel and configure the rate of traffic flow within the tunnel.
- You specify a tunnel rate in Kbps. All circuits in the VP are restricted to the rate that you set.
- The tunnel rate can be a value in the range 0–4294967295, when you specify the rate of traffic flow without the constant bit rate (CBR) service category, and can be a value in the range 1–4294967295, when you specify the rate of traffic flow with the CBR service class. Because the CBR service category guarantees a fixed amount of bandwidth to be allotted to the client, an error message is displayed if you configure a value of 0 for the tunnel rate for CBR traffic flows.
- If any virtual circuits are open within the VPI before the tunnel is created, the router does not execute this command.
- For more information about configuring a shapeless VP tunnel for QoS, see ATM Integrated Scheduler Overview.
- Example
  host1(config-if)#atm vp-tunnel 2 128
- Use the no version to remove the VP tunnel. When circuits are open within the tunnel, the router does not remove the tunnel.
- See atm vp-tunnel.

ds3-scramble

e3-scramble

- Use to scramble the ATM cell payload on a T3 or an E3 interface. DS3 (T3) and E3 scrambling assists clock recovery on the receiving end of the interface.
- Example
  host1(config-if)#ds3-scramble
- Use the no version to disable scrambling.
- See ds3-scramble.
- See e3-scramble.

load-interval

- Use to set the time interval at which the router calculates bit and packet rate counters for the ATM interface.
- You can choose a multiple of 30 seconds, in the range 30–300 seconds.
- Example
  host1(config-if)#load-interval 90
- Use the no version to return to the default setting, 300 seconds.
- See load-interval.

loopback

- Use to place the interface into loopback mode.
- Specify either:
  - diagnostic—Places the interface into internal loopback.
  - line —Places the interface into external loopback.
- Example
  host1(config-if)#loopback diagnostic
- Use the no version to remove any loopback.
- See loopback.