Configuration Tasks

This section describes how to perform the following ATM configuration tasks:

• Creating a Basic Configuration
• Setting Optional Parameters
• Configuring SVCs
• Configuring OAM
• Configuring an NBMA Interface
• Creating an NBMA Static Map
• Assigning Descriptions to Interfaces
• Sending Interface Descriptions to AAA
• Configuring Dynamic ATM 1483 Subinterfaces

Creating a Basic Configuration

To configure ATM, perform the following tasks. (Figure 4 shows the relationship of Steps 1 through 3.)

1. Configure an ATM physical interface.

For ATM interfaces on ERX-7xx models, ERX-14xx models, and the ERX-310 router, use the slot/port format; for example:

host1(config)#interface atm 0/1 

2. Configure an ATM 1483 subinterface.

host1(config-if)#interface atm 0/1.20

3. Configure a PVC by specifying the VCD, the VPI, the VCI, and the encapsulation type.

host1(config-subif)#atm pvc 10 15 22 aal5snap

4. Assign an IP address and subnet mask to the PVC.

host1(config-subif)#ip address 192.32.10.20 255.255.255.0

5. (Optional) Verify your configuration using the appropriate show commands.

host1#show atm interface atm 0/1

host1#show atm vc atm 0/1 10

host1#show atm subinterface atm 0/1.20

Figure 4: Configuring an ATM Interface, Subinterface, and PVC

atm pvc

• Use to configure a PVC on an ATM interface.
• Specify one of the following encapsulation types:

• aal5snap—Specifies an LLC encapsulated circuit; LLC/SNAP header precedes the protocol datagram.
• aal5mux ip—Specifies a VC-based multiplexed circuit. This option is used for IP only.
• aal5autoconfig—Enables autodetection of the 1483 encapsulation (LLC/SNAP or VC multiplexed) for dynamic interfaces. See Chapter 13, Configuring Dynamic Interfaces, for more explanation.
• ilmi—Defines the PVC for ILMI keepalive messages. You can set this option only on major interfaces. Once the PVC is set up for ILMI, use the atm ilmi-keepalive command to cause the router to generate ILMI keepalive messages on the interface.

• You can optionally set the peak, average, and burst sizes. To use VBR-RT or VBR-NRT as the service type, you must specify each of these options.
• The default service type is UBR. To set a different service type, specify one of the following keywords:

• rt—Selects VBR-RT as the service type. You can select rt only if you set the peak, average, and burst parameters.
• cbr—Selects CBR as the service type. You must set the CBR rate in Kbps.

• To enable VC integrity and generation of OAM F5 loopback cells on this circuit, use the oam keyword.
• Example

host1(config-if)#atm pvc 6 0 11 aal5snap cbr 10000

• Use the no version to remove the specified PVC.

interface atm

• Use to configure an ATM interface or subinterface type.
• Specify the ATM interface in the slot/port.subinterface format:

• slot—Number of the chassis slot
• port—Port number on the I/O module; on the OC3-2 GE APS I/O module, you can specify ATM interfaces only in ports 0 and 1; port 2 is reserved for a Gigabit Ethernet interface
• subinterface—Number of the subinterface in the range 1-2147483647

• Specify the type of interface or subinterface: point-to-point or multipoint. Point-to-point is the default.
• Example

host1(config-if)#interface atm 0/1.20

• Use the no version to remove the subinterface or the logical interface.

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

• 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 should use 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

The following are optional tasks that you can perform 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.
• Example

host1(config-if)#atm aal5 shutdown

• Use the no version to enable a disabled interface.

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.

atm atm1483 advisory-rx-speed

• Use to set an advisory receive speed for an ATM 1483 subinterface. This setting has no affect 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.
  

  NOTE: If you specify an advisory receive speed greater than 4294967 kbps, the speed will not be 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.

atm atm1483 mtu

• Use to set the MTU size for an ATM 1483 subinterface.
• The range is 256-9180.
• Use the no version to restore the default size of 9180.

atm atm1483 shutdown

• Use to set an ATM 1483 subinterface administrative state to disabled.
• Use the no version to enable a disabled subinterface.

atm atm1483 snmp trap link-status

• Use to enable SNMP link status traps on an ATM 1483 layer subinterface.
• Use the no version to disable the traps.

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.

atm cac

• Use to enable CAC on the interface. You can set a subscription limit, which lets you oversubscribe the port, and the UBR weight, which lets you limit the number of UBR connections.
• Example

host1(config-if)#atm cac 3000000 ubr 3000

• Use the no version to disable CAC on the interface.

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.

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

atm ilmi-keepalive

• Use to generate ILMI keepalive messages. This value sets the allowable time between poll PDU transmissions if there are no pending sequence data PDUs.
• Example

host1(config-if)#atm ilmi-keepalive 5

• Use the no version to disable the generation of keepalive messages.

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 (the default)
• short—A cable length in the range 226-450

• Example

host1(config-if)#atm lbo long

• Use the no version to restore the default value, short.

atm shutdown

• Use to set an ATM interface administrative state to disabled.
• Example

host1(config-if)#atm shutdown

• Use the no version to enable a disabled interface.

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.

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.

atm uni-version

• Use to specify the UNI version the interface should 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.

atm vc-per-vp

• Use to configure the number of VCs for each VP. The router will not execute this command if 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 and 1024 for T3 ATM line modules. If you enter a value that is below the minimum, the router uses the minimum value.
• Example

host1(config-if)#atm vc-per-vp 128

• Use the no version to restore the default value.

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.
• If any virtual circuits are open within the VPI before the tunnel is created, the router will not execute this command.
• Example

host1(config-if)#atm vp-tunnel 2 128

• Use the no version to remove the VP tunnel. If circuits are open within the tunnel, the router will not remove the 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.

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.

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.

Configuring SVCs

To configure SVCs:

1. Enable ILMI on the ATM interface.

host1(config)#interface atm 4/0

host1(config-if)#atm ilmi-enable

2. Create a PVC with a QSAAL signaling channel on the ATM interface. This PVC performs call setup for the SVC.

host1(config-if)#atm pvc 5 0 5 qsaal

3. Access Subinterface Configuration mode and specify an ATM ESI address.

host1(config-if)#interface atm 4/0.1

host1(config-subif)#atm esi-address 004ff8234002.00

4. Create the SVC and define the SVC parameters, including the destination ATM address, encapsulation method, and traffic parameters.

host1(config-subif)#atm svc nsap 

70.000458ff000b923011f22100.234f89bb0000.00 aal5snap cbr 23961

Once you define an SVC, the router attempts to set up an SVC to this destination with the requested traffic parameters and encapsulation method.

atm esi-address

• Use to specify an ESI address. The ESI address identifies the ATM device attached to the switch. The subinterface uses this address when it responds to ATM SVC signaling setup requests.
• Example

host1(config-subif)#atm esi-address 004ff8234002.00

• Use the no version to remove the ESI address.

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.

atm pvc

• Use with the qsaal keyword to create a QSAAL signaling channel for the SVC.
• Recommended values are VPI=0 and VCI=5.
• Example

host1(config-if)#atm pvc 5 0 5 qsaal

• Use the no version to remove the signaling channel.

atm svc

• Use to configure an SVC on an ATM subinterface.
• You must include the nsap keyword to define the destination ATM NSAP address.
• Specify one of the following encapsulation types:

• aal5snap—Specifies an LLC encapsulated circuit; LLC/SNAP header precedes the protocol datagram.
• aal5mux ip—Specifies a VC-based multiplexed circuit. This option is used for IP only.

• You can optionally set the peak, average, and burst sizes. To use the VBR-RT service type, you must specify each of these options.
• Use the cbr keyword to specify the CBR service type.
• Example

host1(config-subif)#atm svc nsap 

70.000458ff000b923011f22100.234f89bb0000.00

• Use the no version to remove the SVC definition.

Configuring OAM

This section covers:

• Configuring F4 OAM
• Configuring F5 OAM
• Setting a Loopback Location ID
• Setting Up the Router to Ignore Received OAM Cells
• Running ATM Ping

Configuring F4 OAM

The ATM interface does not support sending F4 segment loopback cells, but it does respond to F4 segment loopback cells that it receives.

F4 OAM flows need their own channel, and they are identified by the VCI on which they are sent or received. The following VCIs are reserved for F4 OAM flows for each virtual path, and you cannot open PVCs on them:

• VCI 3—For segment F4 flows
• VCI 4—For end-to-end F4 flows
  

  NOTE: You cannot enable both loopback cells and CC cells at the same time.

  
  

To set up F4 OAM:

1. Enable F4 OAM on an interface or VP. The router enables F4 OAM at the interface level unless you specify a VPI. This example opens both segment and end-to-end F4 OAM circuits on VPI 10.

host1(config-if)#atm oam 10

2. (Optional) Enable only segment or end-to-end loopback.

host1(config-if)#atm oam 10 seg-loopback

host1(config-if)#atm oam 10 end-loopback

3. (Optional) To cause the interface to generate end-to-end loopback cells in addition to receiving and responding to them, set the loopback timer.

See the atm oam command description following this procedure for more information about setting the loopback timer.

host1(config-if)#atm oam 10 end-loopback loopback-timer 20

4. (Optional) Enable CC cell flows.

host1(config-if)#atm oam 10 seg-loopback cc source

atm oam

• Use to configure F4 OAM on an interface or circuit. F4 OAM is configured at the interface level unless you specify a VPI.
• To open F4 OAM on either a segment or end-to-end basis, use the following keywords:

• seg-loopback—Enables F4 segment OAM
• end-loopback—Enables F4 end-to-end OAM
  

  NOTE: If you do not specify either segment or end-to-end loopback, the command applies to both end-to-end and segment F4 OAM circuits.

  
  

• To configure CC cell flow on the PVC, use the following keywords:

• both—Enables the PVC as both the source and the sink endpoints.
• sink—Enables the PVC as the sink endpoint.
• source—Enables the PVC as the source endpoint.
• loopback-timer—When F4 OAM is enabled, the interface or circuit accepts and responds to F4 OAM cells. However, to generate F4 loopback cells, you must configure the loopback timer in the range 0-600 seconds. This timer represents the frequency with which F4 loopback cells are transmitted. You can set the loopback timer only for end-to-end loopback. The time interval is a multiple of 20 and is based on the number of circuits on a single line module with VC integrity enabled. The values are: 20 seconds for 0-999 circuits, 40 seconds for 1000-1999 circuits, 60 seconds for 2000-2999 circuits, and so on. The router uses these values regardless of the value configured for the loopback timer.

• Example 1—Opens both F4 end-to-end and segment OAM circuits for VPI 8

host1(config-if)#atm oam 8 

• Example 2—Opens the F4 end-to-end OAM circuit for VPI 10 and enables sending F4 end-to-end loopback cells on the circuit at a frequency of 20 seconds

host1(config-if)#atm oam 10 end-loopback loopback-timer 20

• Example 3—Opens both F4 end-to-end and segment OAM circuits on all VPs on this interface

host1(config-if)#atm oam

• Example 4—Opens F4 segment OAM circuits on all VPs on this interface

host1(config-if)#atm oam seg-loopback

• Example 5—Opens F4 end-to-end loopback on VPI 12

host1(config-if)#atm oam 12 end-loopback

• Example 6—Opens an F4 segment OAM circuit for VPI 8 and enables CC cell generation on the segment

host1(config-if)#atm oam 8 seg-loopback cc source

• Use the no version to delete F4 OAM circuits. Using the options, you can delete all F4 OAM circuits on the interface, segment or end-to-end F4 OAM circuits, or F4 OAM circuits on a specific VPI.

• Example 1—Deletes all F4 OAM circuits on the interface

host1(config-if)#no atm oam

• Example 2—Deletes all F4 segment OAM circuits on the interface

host1(config-if)#no atm oam segment

• Example 3—Deletes the F4 end-to-end OAM circuit on VPI 8

host1(config-if)#no atm oam 8 end-loopback

Configuring F5 OAM

F5 OAM flows run over existing PVCs. The ATM interface does not support sending F5 segment loopback cells, but it does respond to F5 segment loopback cells that it receives.

NOTE: You cannot enable both loopback cells and CC cells at the same time.

To set up F5 OAM:

1. To enable VC integrity, which causes the ATM interface to periodically send F5 end-to-end loopback cells over a VC, use the oam keyword with the atm pvc command.

You can include the frequency (in seconds) with which the router sends F5 end-to-end loopback cells. See the atm pvc command description following this procedure for more information about setting the F5 OAM frequency.

host1(config-if)#atm pvc 98 38 22 aal5snap oam 300

2. (Optional) To enable CC cell flows on a circuit, use the cc keyword with the atm pvc command. You can enable cell flows on a segment or end-to-end basis, and you can enable the PVC as a sink, source, or both a sink and a source.

host1(config-if)#atm pvc 50 0 50 aal5snap oam cc end-to-end sink 

atm pvc

• Use the atm pvc command with the oam keyword to set up the PVC to periodically transmit F5 end-to-end loopback cells over a VC.
• You can use the oam keyword only if you specify one of the following encapsulation types:

• aal5snap
• aal5mux ip
• aal5autoconfig

• The oam keyword is not available with the aal5all, aal0, ilmi, or qsaal encapsulation types.
• Optionally, you can configure the time interval in the range 0-600 seconds between transmissions of OAM F5 end-to-end loopback cells. The time interval is a multiple of 20 and is based on the number of circuits on a single line module with VC integrity enabled. The values are: 20 seconds for 0-999 circuits, 40 seconds for 1000-1999 circuits, 60 seconds for 2000-2999 circuits, and so on. The router uses these values regardless of the value configured for the time interval.
• Use the following keywords to enable and configure CC cell flows:

• end-to-end—Opens an end-to-end CC cell flow
• segment—Opens a segment CC cell flow
• sink—Enables this VC as a sink point (cell receiver)
• source—Enables this VC as the source point (cell generator)
• both—Enables this VC as both a sink point and a source point

• Example 1—Enables F5 end-to-end loopback cells

host1(config-if)#atm pvc 20 20 20 aal5snap oam 

• Example 2—Enables end-to-end CC cell flow and enables the PVC as the sink

host1(config-if)#atm pvc 5 0 5 aal5auto oam cc end-to-end sink

• Use the no version of the atm pvc command without the oam keyword to disable F5 OAM on the PVC and without the cc keyword to disable CC cell flows on the PVC. For example, the following command disables CC cell flow configured in Example 2.

host1(config-if)#no atm pvc 5 0 5 aal5auto

Setting a Loopback Location ID

To allow other nodes to specifically send OAM loopback cells to the ATM interface, set the location ID of the ATM interface or circuit.

host1(config-if)#atm oam loopback-location 01090708

 NOTE: Because the router is a connection endpoint, the default loopback location ID is all 1s (ones). This command allows you to specify a nondefault value.



 

atm oam loopback-location

• Use to set the location ID of the ATM interface. The location ID is a 4-octet field, and the default value is all 1s (ones).

• You can set a specific value to identify this ATM interface as the intended recipient of OAM loopback cells.
• You can also set the location ID to all 0s (zeros).
• For information about how the router handles loopback cells based on location ID, see Table 10.

• Example

host1(config-if)#atm oam loopback-location 01090708

• Use the no version to return the loopback location ID to the default value, all 1s (ones).

Setting Up the Router to Ignore Received OAM Cells

You can also configure the router to ignore all received OAM cells or to ignore only AIS and RDI cells, which is useful in diagnostic situations when it may be preferable to ignore alarm conditions. The atm oam flush command controls this feature.

NOTE: OAM alarm cell filtering is supported only on OCx/STMx ATM line modules with either the OC3-4 I/O module or the OC12/STM4 I/O module.

atm oam flush

• Use to enable the OAM flush feature. When OAM flush is enabled, the router ignores all OAM cells received on the interface.
• To cause the router to ignore only AIS and RDI cells and to accept all other OAM cells, use the alarm-cells keyword.
• Example

host1(config-if)#atm oam flush

• Use the no version to disable the feature.

Running ATM Ping

Keep in mind the following when you use ATM ping:

• Before you can run ATM ping, you need to add a PVC for the VPI and VCI over which you run the ping.
• Because ATM ping requires the receipt of OAM cells, make sure that the receipt of OAM cells is not disabled (using the atm oam flush command). To reenable the receipt of OAM cells, enter no atm oam flush.
• Disabling receipt of OAM cells during a ping operation stops all outstanding ping operations. You need to manually restart the ping operation once receipt of OAM cells for the interface is enabled.
• Since ATM ping is a dynamic (on-demand) operation, none of the configuration related to ATM ping is saved. To avoid acquiring excessive bandwidth for OAM, the number of outstanding ping operations on each interface is limited to 12.

ping atm interface atm

• Use to send loopback cells from an ATM interface or circuit.
• The VPI and VCI fields determine the type of loopback cells used for the ping operation. By default F5 end-to-end loopback OAM cells are used.

• To send F4 segment loopback cells, set the VCI to 3.
• To send F4 end-to-end loopback cells, set the VCI to 4.

• Use the end-loopback keyword to send the ping to the connection endpoint.
• Use the seg-loopback keyword to send the ping to the first segment point (for example, the next neighbor switch).
• Use the destination option to specify the value of the location ID included in the loopback cell. The location ID is a 16-octet field, and the destination portion is 4 octets. You can set the location ID to a specific destination or to 0s (zeros) or 1s (ones).

• If you set the destination to 0, the loopback location ID in the loopback cell is initialized to all 0s, and each segment point in the network responds to the ping.
• If you set the destination to 1s, the loopback location ID in the loopback cell is initialized to all 1s, and only the connection endpoint responds to the ping.
• If you use the default value of 0xFFFFFFFF, the loopback location ID in the loopback cell is initialized to all 1s.

For information about how the router handles loopback cells based on location ID, see Table 10.

• The count keyword sets the number of OAM loopback cells to send to the destination. The default value is 5. The maximum is 32.
• The timeout keyword sets the amount of time to wait for a response to the sent OAM loopback cell. The default value is 5 seconds.
• The following characters can appear in the display after the ping command has been issued:

• !—Each exclamation point indicates that a reply was received
• .—Each period indicates that the ping timed out while waiting for a reply

• Example 1—This example generates end-to-end loopback cells for VPI=0 and VCI=105 on ATM interface 2/0. The count value is 5 OAM loopback cells, and the timeout value is 2 seconds.

host1#ping atm interface atm 2/0 0 105 end-loopback count 5 timeout 2

Sending 5 53-byte OAM end-to-end loopback Echoes timeout is 2 secs

Press Ctrl+c to stop

!!!!!

Success rate = 100% (5/5), round-trip min/avg/max = 0/4/10 ms

• Example 2—This example generates segment loopback cells for VPI=0 and VCI=105 on ATM interface 2/0. The destination is set to 0xFFFFFFFF, the count value is 3 OAM loopback cells, and the timeout value is 1 second.

host1#ping atm interface atm 2/0 0 105 seg-loopback 0xFFFFFFFF count 3 
timeout 1

Sending 3 53-byte OAM segment loopback Echoes timeout is 1 secs

Press Ctrl+c to stop

!!!

Success rate = 100% (3/3), round-trip min/avg/max = 0/3/10 ms

• There is no no version.

Configuring an NBMA Interface

You configure an ATM NBMA 1483 subinterface in a manner similar to configuring a standard ATM 1483 subinterface. When you specify a subinterface, however, you must select the multipoint option if you plan to add multiple circuits to form an NBMA interface. If you do not select multipoint, the subinterface defaults to point-to-point, and only a single circuit can be affiliated with that subinterface.

You can configure one or more PVCs and associate them with the subinterface you create. Also, you can enable InARP and identify a refresh rate on each specific circuit. For each NMBA interface, either InARP must be enabled, or a static map entry must be provided for each circuit owned by the interface; otherwise, transmitting over that circuit is impossible.

NOTE: NBMA interfaces support only the aal5snap encapsulation.

To configure an NBMA interface:

1. Configure a physical interface.

host1(config)#interface atm 2/0 

2. Configure a 1483 subinterface.

host1(config-if)#interface atm 2/0.2 multipoint

3. Configure PVCs by specifying the VCD, VPI, VCI, and encapsulation type.

host1(config-subif)#atm pvc 1 1 1 aal5snap inarp 10

host1(config-subif)#atm pvc 2 2 2 aal5snap

4. (Optional) Specify InARP and a refresh rate (also optional).

host1(config-subif)#atm pvc 3 3 3 aal5snap inarp 5

host1(config-subif)#atm pvc 4 4 4 aal5snap inarp

5. Assign an IP address and subnet mask to the PVC.

host1(config-subif)#ip address 192.32.10.20 255.255.255.0

6. (Optional) Use the appropriate show commands to verify your configuration.

host1#show atm interface atm 2/0

host1#show atm map

host1#show nbma arp atm 2/0

host1#show atm vc atm 2/0 2

host1#show atm subinterface atm 2/0.2

Creating an NBMA Static Map

Static mapping creates an association between IP address-ATM PVC pairs for one or more member circuits of an ATM 1483 NBMA interface. Not every circuit necessarily gets the required association from a static map.

In the following procedure, you can repeat Step 2 for each circuit you want to map. A map group name that you have not already established can be associated with an interface. When you define the map list, the name will then be associated with that interface. You can perform Steps 3 and 4 before Steps 1 and 2 without affecting the results.

To set up a static map:

1. Create a map list by naming it.

host1(config)#map-list charlie

2. Associate a protocol and an address with a specific virtual circuit.

host1(config-map-list)#ip 192.168.13.13 atm-vc 1 broadcast

3. Specify an ATM port adapter interface.

host1(config-if)#interface atm 2/0

4. Associate the map list with the interface.

host1(config-if)#map-group charlie

atm pvc

• Use to configure a PVC on an ATM interface.
• InARP and refresh rate are optional parameters.
• InARP determines if InARP requests are used and is specified on a per-circuit basis. If you disable InARP, you must use a static map table entry. Transmission over the circuit is not possible unless you use either InARP or static map table entries.
• The default refresh rate is 15 minutes.
• You can configure InARP only if you specify the aal5snap encapsulation type.
• Example

host1(config-if)#atm pvc 6 0 11 aal5snap inarp 10

• Use the no version to remove the specified PVC.

interface atm

• Use to configure an ATM interface or subinterface type.
• Specify the ATM interface in the slot/port.subinterface format.
• For more information, see Creating a Basic Configuration.
• Specify multipoint to identify the subinterface as NBMA.
• Use the no version to remove the subinterface or the logical interface.

ip atm-vc

• Use to associate a protocol and address with a specific virtual circuit.
• Use this command repeatedly for each circuit to be mapped.
• This command is available in Map List Configuration mode only.
• Example

host1(config-map-list)#ip 192.168.13.13 atm-vc 1 broadcast

• Use the no version to remove the association.

map-group

• Use to associate the map list with an NBMA interface when configuring static mapping.
• You can issue this command before or after the map-list command without changing anything.
• This command is available in Interface Configuration mode only.
• See the map-list command.
• Example

host1(config-if)#map-group charlie

• Use the no version to remove the association.

map-list

• Use to create a map list when configuring static mapped NBMA interfaces.
• Limit the name of the map list to no more than 31 characters.
• You can create multiple map lists; however, you can associate only one map list with each physical interface. Each map list can be associated with a single interface.
• If a map list contains an entry for a VCD that was previously configured to run InARP, the map-group command fails. If this is the case, either reconfigure the circuit with InARP disabled, or remove the entry for that circuit from the map list.
• Example

host1(config)#map-list charlie

• Use the no version to remove the map list.

Assigning Descriptions to Interfaces

You can use the description commands to assign a text description or an alias to an interface, which allows that information to be displayed by other show commands.

atm aal5 description

• Use to assign a text description or alias to an ATM AAL5 interface.
• Use the show atm aal5 interface command to display the text description.
• Use the no version to remove the text description or alias.

atm atm1483 description

• Use to assign a text description or alias to an ATM 1483 subinterface.
• The description can be a maximum of 255 characters.
• Use the show atm subinterface command to display the text description.
• Use the no version to remove the text description or alias.

atm description

• Use to assign a text description or alias to the ATM interface.
• The description can be a maximum of 255 characters and can include the # (pound sign) character.
• The first 32 characters of the ATM description are pushed out to RADIUS during authentication and accounting.
• Use the show atm interface command to display the description.
• Use the no version to remove the description or alias.

Sending Interface Descriptions to AAA

During authentication the router sends ATM interface descriptions to AAA. AAA passes the descriptions to RADIUS, and they may appear in the Calling-Station-Id attribute [31]. (For information about RADIUS and the Calling-Station-ID attribute, see JUNOSe Broadband Access Configuration Guide, Chapter 2, Configuring RADIUS Attributes.)

By default, the router sends the major interface descriptions to AAA on the SRP. You can configure the router to send VP interface descriptions in place of the major interface descriptions, or to send ATM 1483 subinterface descriptions to AAA on the line module. As a result, the VP or ATM 1483 subinterface descriptions can provide a convenient way to identify or group broadband access subscribers.

If you set up multiple interface descriptions, they have the following precedence:

1. ATM 1483 subinterface description
2. VP interface description
3. Major interface description

Assigning Descriptions to Virtual Paths

To assign a description to an individual VP on an ATM interface, use the atm vp-description command. The VP description does not affect existing descriptions configured for the ATM interface or ATM 1483 subinterface on which the VP resides. However, if you delete the ATM interface, the descriptions of all VPs residing on that interface are also deleted. In addition, if you decrease the VPI range by issuing the atm vc-per-vp command, the router deletes the descriptions of any VPs that are removed.

To display the VP description, use the show atm vp-description command, as described in ATM show Commands. Although you need not configure a VP tunnel to specify a VP description, the router also displays the VP description in the output of the show atm vp-tunnel command.

Exporting ATM 1483 Subinterface Descriptions

To assign a description to an ATM 1483 subinterface and configure the router to send the ATM 1483 VC interface descriptions to the line module:

1. Configure a text description for ATM 1483 subinterfaces with the atm atm1483 description command. This description is included in the interface identifier that is sent to AAA.

To configure this feature for ATM 1483 subinterfaces, enter this command in Profile Configuration mode. See Configuring ATM 1483 Dynamic Subinterfaces in Chapter 13, Configuring Dynamic Interfaces.

host1(config-subif)#atm atm1483 description VC_atm1

2. Set up the router to export ATM 1483 VC interface descriptions to the line module.

host1(config)#atm atm1483 export-subinterface-description 

3. (Optional) Display the configuration of the export ATM 1483 VC interface descriptions feature with the show atm atm1483 command.

host1#show atm atm1483

ATM1483 IF Descriptions exported 

4. (Optional) Display the interface descriptions with the show atm subinterface atm command.

atm atm1483 description

• Use to assign a text description or alias to an ATM 1483 subinterface.
• The description can be a maximum of 255 characters.
• Use the no version to remove the text description or alias.

atm atm1483 export-subinterface-description

• Use to export ATM 1483 VC interface descriptions to the line module. Descriptions for ATM 1483 subinterfaces are configured with the atm atm1483 description command.
• The description can have up to 255 characters; however, when the description is sent to the line module, it is truncated to 32 characters.
• Example

host1(config)#atm atm1483 export-subinterface-description 

• Use the no version to restore the default, ATM 1483 interface descriptions are not exported to the line module.

atm vp-description

• Use to assign a text description to an individual VP on an ATM interface or subinterface.
• You must specify the VPI of the VP to which you want to assign the description.
• The description string can be a maximum of 32 characters.
• The VP description is stored in NVS and persists after a reboot.
• Use the show atm vp-description command to display the text description.
• Example

host1(config-if)#atm vp-description 2 vpi2Subscribers

• Use the no version to restore the default value, a null string.

Configuring Dynamic ATM 1483 Subinterfaces

As an alternative to the static ATM interface configurations described in this chapter, you can also configure dynamic ATM 1483 subinterfaces over static ATM AAL5 interfaces over ATM. Dynamic ATM 1483 subinterfaces can perform autodetection and dynamic creation of the following upper-layer encapsulation types:

• Bridged Ethernet
• IP
• PPP
• PPPoE

For details, see Configuring ATM 1483 Dynamic Subinterfaces in Chapter 13, Configuring Dynamic Interfaces.