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Cisco IOS Wide-Area Networking Configuration Guide, Release 12.2
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About Cisco IOS Software Documentation
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Using Cisco IOS Software
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Wide-Area Networking Overview
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Configuring ATM
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Configuring Broadband Access: PPP and Routed Bridge Encapsulation
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Configuring Frame Relay
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Configuring Frame Relay-ATM Interworking
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Configuring SMDS
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Configuring X.25 and LAPB
- Appendixes
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Index
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Table Of Contents
Mapping a Protocol Address to a PVC
Configuring the AAL and Encapsulation Type
Configuring PVC Traffic Parameters
Configuring Generation of End-to-End F5 OAM Loopback Cells
to Verify ConnectivityConfiguring Broadcast on a PVC
Configuring Communication with the ILMI
Configuring the PVC That Performs SVC Call Setup
Configuring the ESI and Selector Fields
Configuring the Complete NSAP Address
Configuring ATM UNI Version Override
Configuring the Idle Timeout Interval
Configuring Point-to-Multipoint Signalling
Configuring IP Multicast over ATM Point-to-Multipoint Virtual Circuits
Configuring SVC Traffic Parameters
Configuring Strict Traffic Shaping
Configuring Generation of End-to-End F5 OAM Loopback Cells to Verify Connectivity
Configuring Broadcast on an SVC
Assigning a VC Class to an SVC
Setting the Connection Control Timer
Setting the Transmitter and Receiver Windows
Configuring OAM Management for PVCs
Configuring OAM Management for SVCs
Configuring Classical IP and ARP over ATM
Configuring Classical IP and ARP in an SVC Environment
Configuring the Router as an ATM ARP Client
Configuring the Router as an ATM ARP Server
Configuring Classical IP and Inverse ARP in a PVC Environment
Configuring Rate Queue Tolerance
Configuring a Permanent Rate Queue
Setting the Exception Queue Length
Configuring the Maximum Number of Channels
Limiting the Number of Virtual Circuits
Setting the Source of the Transmit Clock
Configuring ATM Subinterfaces for SMDS Networks
Limiting the Message Identifiers Allowed on Virtual Circuits
Setting the Virtual Path Filter Register
Configuring Fast-Switched Transparent Bridging for SNAP PVCs
Configuring Inverse Multiplexing over ATM
General Description of ATM T1/E1 IMA
Configuring an ATM Interface for IMA Operation
Verifying an ATM Interface Configured for IMA Operation
Verifying IMA Group Configuration
Configuring ATM E.164 Auto Conversion
Configuring Circuit Emulation Services
Configuring CES on the OC-3/STM-1 ATM Circuit Emulation Service Network Module
OC-3/STM-1 ATM Circuit Emulation Service Network Module Restrictions
Configuring the T1/E1 Controller
Verifying CES Configuration on the OC-3/STM-1 ATM Circuit Emulation Service Network Module
Configuring CES on the ATM-CES Port Adapter
Configuring Unstructured (Clear Channel) CES Services
Configuring Structured (N x 64) CES Services
Configuring Channel-Associated Signalling (for Structured CES Services Only)
Configuring Network Clock Source and Priorities
Configuring Virtual Path Shaping
Configuring ATM Access over a Serial Interface
Enabling ATM-DXI Encapsulation
Mapping Protocol Addresses to the ATM-DXI PVC
Monitoring and Maintaining the ATM-DXI Serial Interface
Troubleshooting the ATM Interface
Monitoring and Maintaining the ATM Interface
PVC with AAL5 and LLC/SNAP Encapsulation Examples
PVCs in a Fully Meshed Network Example
Configuring an ABR PVC Example
Configuring PVC Discovery Example
Configuring Generation of End-to-End F5 OAM Loopback Cells Example
Configuring PVC Trap Support Example
Configuring Communication with the ILMI Example
SVCs in a Fully Meshed Network Example
SVCs with Multipoint Signalling Example
Configuring SVC Traffic Parameters Example
ILMI Management on an ATM PVC Example
OAM Management on an ATM PVC Example
OAM Management on an ATM SVC Example
Configuring ATM ARP Client in an SVC Environment Example
Configuring ATM ARP Server in an SVC Environment Example
Configuring ATM Inverse ARP in a PVC Environment Example
PVC with AAL3/4 and SMDS Encapsulation Examples
Transparent Bridging on an AAL5-SNAP PVC Example
Inverse Multiplexing over ATM Examples
E1 IMA on Multiport T1/E1 ATM Network Module Example
T1 IMA on Multiport T1/E1 ATM Network Module Example
T1 IMA on Multiport T1/E1 ATM Port Adapter Example
Configuring ATM E.164 Auto Conversion Example
Circuit Emulation Service Examples
Configuring CES on an OC-3/STM-1 ATM Circuit Emulation Services Network Module Example
Configuring CES on an ATM-CES Port Adapter Example
Configuring Network Clock Source Priority Example
Configuring Virtual Path Shaping Example
ATM Access over a Serial Interface Example
ATM Port Adapters Connected Back-to-Back Example
Configuring ATM
This chapter describes how to configure ATM on the Cisco 2600 series, Cisco 3600 series, Cisco 4500, Cisco 4700, Cisco 7100, Cisco 7200 series, Cisco 7500 and Cisco 12000 series routers. For further general information about ATM, see the chapter "Wide-Area Networking Overview" at the beginning of this book.
For a complete description of the ATM commands in this chapter, refer to the chapter "ATM Commands" in the Cisco IOS Wide-Area Networking Command Reference. To locate documentation of other commands that appear in this chapter, use the command reference master index or search online.
To identify the hardware platform or software image information associated with a feature, use the Feature Navigator on Cisco.com to search for information about the feature or refer to the software release notes for a specific release. For more information, see the section "Identifying Supported Platforms" in the chapter "Using Cisco IOS Software."
For information on the following related topics, see the corresponding Cisco publications:
Configuring routers that use a serial interface for ATM access through an ATM data service unit (ADSU)
"Configuring ATM Access over a Serial Interface" section later in this chapter
Referencing Switched Multimegabit Data Service (SMDS) support
"SMDS Commands" chapter in the Cisco IOS Wide-Area Networking Command Reference
Configuring LAN emulation (LANE) for ATM
"Configuring LAN Emulation" chapter in the Cisco IOS Switching Services Configuration Guide
Configuring IP to ATM class of service (CoS)
"IP to ATM CoS Overview" and "Configuring IP to ATM CoS" chapters in the Cisco IOS Quality of Service Solutions Configuration Guide
Configuring PPP over ATM
"Configuring PPP over ATM" section in the "Configuring Broadband Access: PPP and Routed Bridge Encapsulation" chapter in this book
Configuring PPP over Ethernet (PPPoE) over ATM
"Configuring PPPoE over ATM" section in the "Configuring Broadband Access: PPP and Routed Bridge Encapsulation" chapter in this book
Note
Beginning in Cisco IOS Release 11.3, all commands supported on the Cisco 7500 series routers are also supported on Cisco 7000 series routers equipped with RSP7000.
ATM Configuration Task List
To configure ATM, complete the tasks in the following sections. The first task is required, and then you must configure at least one PVC or SVC. The virtual circuit options you configure must match in three places: on the router, on the ATM switch, and at the remote end of the PVC or SVC connection. The remaining tasks are optional.
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See the section "ATM Configuration Examples" at the end of this chapter for configuration examples.
Enabling the ATM Interface
This section describes how to configure an ATM interface. For the AIP, all ATM port adapters, and the 1-port ATM-25 network module, the port number is always 0. For example, the slot/port address of an ATM interface on an AIP installed in slot 1 is 1/0.
To configure the ATM interface, use the following commands beginning in privileged EXEC mode:
To enable the ATM interface, use the following command in interface configuration mode:
Router(config-if)# no shutdown
Changes the shutdown state to up and enables the ATM interface, thereby beginning the segmentation and reassembly (SAR) operation on the interface.
The no shutdown command passes an enable command to the ATM interface, which then begins segmentation and reassembly (SAR) operations. It also causes the ATM interface to configure itself based on the previous configuration commands sent.
Configuring PVCs
To use a permanent virtual circuit (PVC), you must configure the PVC into both the router and the ATM switch. PVCs remain active until the circuit is removed from either configuration.
Note
All virtual circuit characteristics listed in the chapter "Wide-Area Networking Overview" apply to these PVCs. When a PVC is configured, all the configuration options are passed on to the ATM interface. These PVCs are writable into the nonvolatile RAM (NVRAM) as part of the Route Processor (RP) configuration and are used when the RP image is reloaded.
Some ATM switches might have point-to-multipoint PVCs that do the equivalent of broadcasting. If a point-to-multipoint PVC exists, then that PVC can be used as the sole broadcast PVC for all multicast requests.
To configure a PVC, perform the tasks in the following sections. The first two tasks are required; the other tasks are optional.
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Creating a PVC
To create a PVC on the ATM interface and enter interface-ATM-VC configuration mode, use the following command beginning in interface configuration mode:
Note
Once you specify a name for a PVC, you can reenter the interface-ATM-VC configuration mode by simply entering pvc name.
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See examples of PVC configurations in the section "ATM Configuration Examples" at the end of this chapter.
Mapping a Protocol Address to a PVC
The ATM interface supports a static mapping scheme that identifies the network address of remote hosts or routers. This section describes how to map a PVC to an address, which is a required task for configuring a PVC.
To map a protocol address to a PVC, use the following command in interface-ATM-VC configuration mode:
Router(config-if-atm-vc)# protocol protocol protocol-address [[no] broadcast]
Maps a protocol address to a PVC.
Note
See examples of PVC configurations in the section "ATM Configuration Examples" at the end of this chapter.
Configuring the AAL and Encapsulation Type
To configure the ATM adaptation layer (AAL) and encapsulation type, use the following command beginning in interface-ATM-VC configuration mode:
Router(config-if-atm-vc)# encapsulation aal5encap
Configures the ATM adaptation layer (AAL) and encapsulation type.
For a list of AAL types and encapsulations supported for the aal-encap argument, refer to the encapsulation aal5 command in the "ATM Commands" chapter of the Cisco IOS Wide-Area Networking Command Reference. The global default is AAL5 with SNAP encapsulation.
Configuring PVC Traffic Parameters
The supported traffic parameters are part of the following service categories: Available Bit Rate (ABR), Unspecified Bit Rate (UBR), UBR+, Variable Bit Rate Non Real-Time (VBR-NRT), and real-time Variable Bit Rate (VBR). Only one of these categories can be specified per PVC connection so if a new one is entered, it will replace the existing one.
To configure PVC traffic parameters, use one of the following commands beginning in interface-ATM-VC configuration mode:
The -pcr and -mcr arguments are the peak cell rate and minimum cell rate, respectively. The -scr and -mbs arguments are the sustainable cell rate and maximum burst size, respectively.
For an example of how to configure an ABR PVC, refer to the section "Configuring an ABR PVC Example" at the end of this chapter.
For a description of how to configure traffic parameters in a VC class and apply the VC class to an ATM interface or subinterface, refer to the section "Configuring VC Classes."
Note
For ABR VCs, you can optionally configure the amount that the cell transmission rate increases or decreases in response to flow control information from the network or destination. To configure this option, use the following command in interface-ATM-VC configuration mode:
Router(config-if-atm-vc)# atm abr rate-factor [rate-increase-factor] [rate-decrease-factor]
Specifies the ABR rate factors. The default increase and decrease rate factors is 1/16.
For an example of configuring an ABR PVC, see the section "Configuring an ABR PVC Example" later in this chapter.
Configuring PVC Discovery
You can configure your router to automatically discover PVCs that are configured on an attached adjacent switch. The discovered PVCs and their traffic parameters are configured on an ATM main interface or subinterface that you specify. Your router receives the PVC parameter information using Interim Local Management Interface (ILMI).
To configure PVC discovery on an ATM interface, use the following commands beginning in global configuration mode:
Step 1
Router(config)# interface atm slot/0
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Router(config)# interface atm slot/port-adapter/0
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Router(config)# interface atm number
Specifies the ATM interface using the appropriate format of the interface atm command.1
Step 2
Router(config-if)# pvc [name] 0/16 ilmi
Configures an ILMI PVC on the main interface.
Step 3
Router(config-if-atm-vc)# exit
Returns to interface configuration mode.
Step 4
Router(config-if)# atm ilmi-pvc-discovery [subinterface]
Configures PVC Discovery on the main interface and optionally specifies that discovered PVCs will be assigned to a subinterface.
Step 5
Router(config-if)# exit
Returns to global configuration mode.
Step 6
Router(config)# interface atm slot/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm slot/port-adapter/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm number[.subinterface-number {multipoint | point-to-point}]
Specifies the ATM main interface or subinterface that discovered PVCs will be assigned to.
Step 7
Router(config-subif)# ip address ip-address mask
(Optional) Specifies the protocol address for the subinterface.
1 To determine the correct form of the interface atm command, consult your ATM network module, port adapter, or router documentation.
Use the subinterface keyword in Step 4 if you want the discovered PVCs to reside on an ATM subinterface that you specify in Step 6. The discovered PVCs are assigned to the subinterface number that matches the VPI number of the discovered PVC. For example, if subinterface 2/0.1 is specified using the interface atm command in Step 6, then all discovered PVCs with a VPI value of 1 will be assigned to this subinterface. For an example, see the section "Configuring PVC Discovery Example" later in this chapter.
Repeat Steps 6 and 7 if you want discovered PVCs to be assigned to more than one subinterface. If no subinterfaces are configured, discovered PVCs will be assigned to the main interface specified in Step 1.
For an example of configuring PVC discovery, refer to the section "Configuring PVC Discovery Example" at the end of this chapter.
Enabling Inverse ARP
Inverse ARP is enabled by default when you create a PVC using the pvc command. Once configured, a protocol mapping between an ATM PVC and a network address is learned dynamically as a result of the exchange of ATM Inverse ARP packets.
Inverse ARP is supported on PVCs running IP or IPX and no static map is configured. If a static map is configured, Inverse ARP will be disabled.
To enable Inverse ARP on an ATM PVC, use the following commands beginning in global configuration mode:
Step 1
Router(config)# interface atm slot/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm slot/port-adapter/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm number[.subinterface-number {multipoint | point-to-point}]
Specifies the ATM interface using the appropriate format of the interface atm command.1
Step 2
Router(config-if)# pvc [name] vpi/vci
Specifies an ATM PVC by name (optional) and VPI/VCI numbers.
Step 3
Router(config-if-atm-vc)# encapsulation aal5snap
Configures AAL5 LLC-SNAP encapsulation if it is not already configured.
Step 4
Router(config-if-atm-vc)# inarp minutes
(Optional) Adjusts the Inverse ARP time period.
1 To determine the correct form of the interface atm command, consult your ATM network module, port adapter, or router documentation.
When PVC discovery is enabled on an active PVC and the router terminates that PVC, the PVC will generate an ATM Inverse ARP request. This allows the PVC to resolve its own network addresses without configuring a static map.
Address mappings learned through Inverse ARP are aged out. However, mappings are refreshed periodically. This period is configurable using the inarp command, which has a default of 15 minutes.
You can also enable Inverse ARP using the protocol command. This is necessary only if you disabled Inverse ARP using the no protocol command. For more information about this command, refer to the "ATM Commands" chapter in the Cisco IOS Wide-Area Networking Command Reference.
For an example of configuring Inverse ARP, see the section "Enabling Inverse ARP Example" at the end of this chapter.
Configuring Generation of End-to-End F5 OAM Loopback Cells
to Verify ConnectivityYou can optionally configure the PVC to generate end-to-end F5 OAM loopback cells to verify connectivity on the virtual circuit. The remote end must respond by echoing back such cells. If OAM response cells are missed (indicating the lack of connectivity), the PVC state goes down. If all the PVCs on a subinterface go down, the subinterface goes down.
To configure transmission of end-to-end F5 OAM cells on a PVC, use the following commands in interface-ATM-VC configuration mode:
Use the up-count argument to specify the number of consecutive end-to-end F5 OAM loopback cell responses that must be received in order to change a PVC connection state to up. Use the down-count argument to specify the number of consecutive end-to-end F5 OAM loopback cell responses that are not received in order to tear down a PVC. Use the retry-frequency argument to specify the frequency (in seconds) that end-to-end F5 OAM loopback cells should be transmitted when a change in UP/DOWN state is being verified. For example, if a PVC is up and a loopback cell response is not received after the frequency (in seconds) specified using the oam-pvc command, then loopback cells are sent at the retry-frequency to verify whether or not the PVC is down.
For information about managing PVCs using OAM, see the section "Configuring OAM Management" later in this chapter.
For an example of OAM loopback cell generation, see the section "Configuring Generation of End-to-End F5 OAM Loopback Cells Example" at the end of this chapter.
Configuring Broadcast on a PVC
To send duplicate broadcast packets for all protocols configured on a PVC, use the following command in interface-ATM-VC configuration mode:
Router(config-if-atm-vc)# broadcast
Sends duplicate broadcast packets for all protocols configured on a PVC.
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Assigning a VC Class to a PVC
By creating a VC class, you can preconfigure a set of default parameters that you may apply to a PVC. To create a VC class, refer to the section "Configuring VC Classes" later in this chapter.
Once you have created a VC class, use the following command in interface-ATM-VC configuration mode to apply the VC class to a PVC:
The vc-class-name argument is the same as the name argument you specified when you created a VC class using the vc-class atm command. Refer to the section "Configuring VC Classes" later in this chapter for a description of how to create a VC class.
Configuring PVC Trap Support
You can configure the PVC to provide failure notification by sending a trap when a PVC on an ATM interface fails or leaves the UP operational state.
PVC Failure Notification
Only one trap is generated per hardware interface, within the specified interval defined by the interval "atmIntPvcNotificationInterval". If other PVCs on the same interface go DOWN during this interval, traps are generated and held until the interval has elapsed. Once the interval has elapsed, the traps are sent if the PVCs are still DOWN.
No trap is generated when a PVC returns to the UP state after having been in the DOWN state. If you need to detect the recovery of PVCs, you must use the SNMP management application to regularly poll your router.
PVC Status Tables
When PVC trap support is enabled, the SNMP manager can poll the SNMP agent to get PCV status information. The table "atmInterfaceExtTable" provides PVC status on an ATM interface. The table "atmCurrentlyFailingPVclTable" provides currently failing and previously failed PVC time-stamp information.
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Prerequisites
Before you enable PVC trap support, you must configure SNMP support and an IP routing protocol on your router. See the "ATM Configuration Examples" section later in this document. For more information about configuring SNMP support, refer to the chapter "Configuring SNMP Support" in the Cisco IOS Configuration Fundamentals Configuration Guide. For information about configuring IP routing protocols, refer to the section "IP Routing Protocols" in the Cisco IOS IP Configuration Guide.
To receive PVC failure notification and access to PVC status tables on your router, you must have the Cisco PVC trap MIB called CISCO-IETF-ATM2-PVCTRAP-MIB.my compiled in your NMS application. You can find this MIB on the Web at Cisco's MIB website that has the URL http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
Enabling PVC Trap Support
When you configure PVC trap support, you must also enable OAM management on the PVC. To enable PVC trap support and OAM management, use the following commands beginning in global configuration mode:
Step 1
Router(config)# snmp-server enable traps atm pvc interval seconds fail-interval seconds
Enables PVC trap support.
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Router(config)# interface atm slot/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm slot/port-adapter/0[.subinterface-number {multipoint | point-to-point}]
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Router(config)# interface atm number[.subinterface-number {multipoint | point-to-point}]
Specifies the ATM interface using the appropriate form of the interface atm command.1
Step 3
Router(config-if)# pvc [name] vpi/vci
Enables the PVC.
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Router(config-if-atm-vc)# oam-pvc manage
Enables end-to-end OAM management for an ATM PVC.
1 To determine the correct form of the interface atm command, consult your ATM network module, port adapter, or router documentation.
For more information on OAM management, see the section "Configuring OAM Management" later in this chapter.
The new objects in this feature are defined in the IETF draft The Definitions of Supplemental Managed Objects for ATM Management, which is an extension to the AToM MIB (RFC 1695).
For an example of configuring PVC trap support, see the section "Configuring PVC Trap Support Example" at the end of this chapter.
Configuring SVCs
ATM switched virtual circuit (SVC) service operates much like X.25 SVC service, although ATM allows much higher throughput. Virtual circuits are created and released dynamically, providing user bandwidth on demand. This service requires a signalling protocol between the router and the switch.
The ATM signalling software provides a method of dynamically establishing, maintaining, and clearing ATM connections at the User-Network Interface (UNI). The ATM signalling software conforms to ATM Forum UNI 3.0 or ATM Forum UNI 3.1 depending on what version is selected by ILMI or configuration.
In UNI mode, the user is the router and the network is an ATM switch. This is an important distinction. The Cisco router does not perform ATM-level call routing. Instead, the ATM switch does the ATM call routing, and the router routes packets through the resulting circuit. The router is viewed as the user and the LAN interconnection device at the end of the circuit, and the ATM switch is viewed as the network.
Figure 2 illustrates the router position in a basic ATM environment. The router is used primarily to interconnect LANs via an ATM network. The workstation connected directly to the destination ATM switch illustrates that you can connect not only routers to ATM switches, but also any computer with an ATM interface that conforms to the ATM Forum UNI specification.
Figure 2 Basic ATM Environment
To use SVCs, complete the tasks in the following sections:
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The tasks in the following sections are optional SVC tasks for customizing your network. These tasks are considered advanced; the default values are almost always adequate. You should not have to perform these tasks unless you need to customize your particular SVC connection.
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Configuring Communication with the ILMI
In an SVC environment, you must configure a PVC for communication with the Integrated Local Management Interface (ILMI) so the router can receive SNMP traps and new network prefixes. The recommended vpi and vci values for the ILMI PVC are 0 and 16, respectively. To configure ILMI communication, use the following command in interface configuration mode:
Router(config-if)# pvc [name] 0/16 ilmi
Creates an ILMI PVC on an ATM main interface.
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Once you have configured an ILMI PVC, you can optionally enable the ILMI keepalive function by using the following command in interface configuration mode:
Router(config-if)# atm ilmi-keepalive [seconds]
Enables ILMI keepalives and sets the interval between keepalives.
No other configuration steps are required.
ILMI address registration for receipt of SNMP traps and new network prefixes is enabled by default. The ILMI keepalive function is disabled by default; when enabled, the default interval between keepalives is 3 seconds.
For an example of configuring ILMI, see the section "Configuring Communication with the ILMI Example" in the "ATM Configuration Examples" section at the end of this chapter.
Configuring the PVC That Performs SVC Call Setup
Unlike X.25 service, which uses in-band signalling (connection establishment done on the same circuit as data transfer), ATM uses out-of-band signalling. One dedicated PVC exists between the router and the ATM switch, over which all SVC call establishment and call termination requests flow. After the call is established, data transfer occurs over the SVC, from router to router. The signalling that accomplishes the call setup and teardown is called Layer 3 signalling or the Q.2931 protocol.
For out-of-band signalling, a signalling PVC must be configured before any SVCs can be set up. Figure 3 illustrates that a signalling PVC from the source router to the ATM switch is used to set up two SVCs. This is a fully meshed network; workstations A, B, and C all can communicate with each other.
Figure 3 One or More SVCs Require a Signalling PVC
To configure the signalling PVC for all SVC connections, use the following command in interface configuration mode:
Router(config-if)# pvc [name] vpi/vci qsaal
Configures the signalling PVC for an ATM main interface that uses SVCs.
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The VPI and VCI values must be configured consistently with the local switch. The standard value for VPI and VCI are 0 and 5, respectively.
See the section "SVCs in a Fully Meshed Network Example" at the end of this chapter for a sample ATM signalling configuration.
Configuring the NSAP Address
Every ATM interface involved with signalling must be configured with a network service access point (NSAP) address. The NSAP address is the ATM address of the interface and must be unique across the network.
To configure an NSAP address, complete the tasks described in one of the following sections:
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Configuring the ESI and Selector Fields
If the switch is capable of delivering the NSAP address prefix to the router by using ILMI, and the router is configured with a PVC for communication with the switch via ILMI, you can configure the endstation ID (ESI) and selector fields using the atm esi-address command. The atm esi-address command allows you to configure the ATM address by entering the ESI (12 hexadecimal characters) and the selector byte (2 hexadecimal characters). The NSAP prefix (26 hexadecimal characters) is provided by the ATM switch.
To configure the router to get the NSAP prefix from the switch and use locally entered values for the remaining fields of the address, use the following commands beginning in interface configuration mode:
The recommended vpi and vci values for the ILMI PVC are 0 and 16, respectively.
You can also specify a keepalive interval for the ILMI PVC. See the "Configuring Communication with the ILMI" section earlier in this chapter for more information.
To see an example of setting up the ILMI PVC and assigning the ESI and selector fields of an NSAP address, see the section "SVCs with Multipoint Signalling Example" at the end of this chapter.
Configuring the Complete NSAP Address
When you configure the ATM NSAP address manually, you must enter the entire address in hexadecimal format because each digit entered represents a hexadecimal digit. To represent the complete NSAP address, you must enter 40 hexadecimal digits in the following format:
XX.XXXX.XX.XXXXXX.XXXX.XXXX.XXXX.XXXX.XXXX.XXXX.XX
Note
Because the interface has no default NSAP address, you must configure the NSAP address for SVCs. To set the ATM interface's source NSAP address, use the following command in interface configuration mode:
Router(config-if)# atm nsap-address nsap-address
Configures the ATM NSAP address for an interface.
The atm nsap-address and atm esi-address commands are mutually exclusive. Configuring the router with the atm nsap-address command negates the atm esi-address setting, and vice versa. For information about using the atm esi-address command, see the preceding section "Configuring the ESI and Selector Fields."
See an example of assigning an NSAP address to an ATM interface in the section "ATM NSAP Address Example" at the end of this chapter.
Creating an SVC
To create an SVC, use the following commands beginning in interface configuration mode:
Once you specify a name for an SVC, you can reenter interface-ATM-VC configuration mode by simply entering the svc name command; you can remove an SVC configuration by entering the no svc name command.
For a list of AAL types and encapsulations supported for the aal-encap argument, refer to the encapsulation aal5 command in the "ATM Commands" chapter of the Cisco IOS Wide-Area Networking Command Reference. The default is AAL5 with SNAP encapsulation.
Configuring ATM UNI Version Override
Normally, when ILMI link autodetermination is enabled on the interface and is successful, the router takes the user-network interface (UNI) version returned by ILMI. If the ILMI link autodetermination process is unsuccessful or ILMI is disabled, the UNI version defaults to 3.0. You can override this default by using the atm uni-version command. The no form of the command sets the UNI version to the one returned by ILMI if ILMI is enabled and the link autodetermination is successful. Otherwise, the UNI version will revert to 3.0. To override the ATM UNI version used by the router, use the following command in interface configuration mode:
Router(config-if)# atm uni-version version-number
Overrides UNI version used by router.
No other configuration steps are required.
Configuring the Idle Timeout Interval
You can specify an interval of inactivity after which any idle SVC on an interface is torn down. This timeout interval might help control costs and free router memory and other resources for other uses.
To change the idle timeout interval, use the following command in interface-ATM-VC configuration mode:
Router(config-if-atm-vc)# idle-timeout seconds [minimum-rate]
Configures the interval of inactivity after which an idle SVC will be torn down.
In addition to configuring the interval of inactivity, you can optionally specify the minimum-rate in kilobits per second (kbps). This is the minimum traffic rate required on an ATM SVC to maintain the connection.
Configuring Point-to-Multipoint Signalling
Point-to-multipoint signalling (or multicasting) allows the router to send one packet to the ATM switch and have the switch replicate the packet to the destinations. It replaces pseudobroadcasting on specified virtual circuits for protocols configured for broadcasting.
You can configure multipoint signalling on an ATM interface after you have mapped protocol addresses to NSAPs and configured one or more protocols for broadcasting.
After multipoint signalling is set, the router uses the SVC configurations that have the broadcast keyword set to establish multipoint calls. The call is established to the first destination with a Setup message. Additional parties are added to the call with AddParty messages each time a multicast packet is sent. One multipoint call will be established for each logical subnet of each protocol that has the broadcast keyword set.
To configure multipoint signalling on an ATM interface, use the following commands beginning in global configuration mode:
Step 1
Router(config)# interface atm slot/0
or
Router(config)# interface atm slot/port-adapter/0
or
Router(config)# interface atm number
Specifies the ATM interface using the appropriate format of the interface atm command.1
Step 2
Router(config-if)# pvc [name] 0/5 qsaal
Configures the signalling PVC for an ATM main interface that uses SVCs.
Step 3
Router(config-if-atm-vc)# exit
Returns to interface configuration mode.
Step 4
Router(config-if-atm-vc)# pvc [name] 0/16 ilmi
and
Router(config-if-atm-vc)# exit
(Optional) Configures an ILMI PVC on an ATM main interface and returns to interface configuration mode. This task is required if you configure the ATM NSAP address in Step 5 by configuring the ESI and selector fields.
Step 5
Router(config-if)# atm nsap-address nsap-address
or
Router(config-if)# atm esi-address esi.selector
Configures the complete NSAP address manually.
or
Configures the ESI and selector fields. To use this method, you must configure Step 4 first.
Step 6
Router(config-if)# svc [name] nsap address
Create san SVC and specifies the destination NSAP address. Enters interface-ATM-VC mode.
Step 7
Router(config-if-atm-vc)# protocol protocol protocol-address broadcast
Provides a protocol address for the interface and enables broadcasting.
Step 8
Router(config-if-atm-vc)# exit
Returns to interface configuration mode.
Step 9
Router(config-if)# atm multipoint-signalling
Enables multipoint signalling to the ATM switch.
Step 10
Router(config-if)# atm multipoint-interval interval
(Optional) Limits the frequency of sending AddParty messages.
1 To determine the correct form of the interface atm command, consult your ATM network module, port adapter, or router documentation.
If multipoint virtual circuits are closed, they are reopened with the next multicast packet. Once the call is established, additional parties are added to the call when additional multicast packets are sent. If a destination never comes up, the router constantly attempts to add it to the call by means of multipoint signalling.
For an example of configuring multipoint signalling on an interface that is configured for SVCs, see the section "SVCs with Multipoint Signalling Example" at the end of this chapter.
Configuring IP Multicast over ATM Point-to-Multipoint Virtual Circuits
This task is documented in the "Configuring IP Multicast Routing" chapter of the Cisco IOS IP Configuration Guide.
Configuring SVC Traffic Parameters
The tasks in this section are optional and advanced. The ATM signalling software can specify to the ATM interface on the router and the switch a limit on how much traffic the source router will be sending. It provides this information in the form of traffic parameters. (These parameters have default values.) The ATM switch in turn sends these values as requested by the source to the ATM destination node. If the destination cannot provide such capacity levels, the call may fail. (For Cisco router series behavior, see the per-interface atm sig-traffic-shaping strict command in the Cisco IOS Wide-Area Networking Command Reference.) There is a single attempt to match traffic values.
The supported traffic parameters are part of the following service categories: Unspecified Bit Rate (UBR), UBR+, and Variable Bit Rate Non Real-Time (VBR-NRT). Only one of these categories can be specified per SVC connection so if a new one is entered, it will replace the existing one. The commands used to specify the service category and traffic values are identical to those used when you create a PVC.
To configure traffic parameters on an SVC, use the following commands beginning in global configuration mode:
Step 1
Router(config)# interface atm slot/0[.subinterface-number {multipoint | point-to-point}]
or
Router(config)# interface atm slot/port-adapter/0[.subinterface-number {multipoint | point-to-point}]
or
Router(config)# interface atm number[.subinterface-number {multipoint | point-to-point}]
Specifies the ATM interface using the appropriate format of the interface atm command.1
Step 2
Router(config-if)# svc [name] nsap address
Creates an SVC and specifies the destination NSAP address.
Step 3
Router(config-if-atm-vc)# protocol protocol protocol-address [[no] broadcast]
Maps a destination protocol address to an SVC.
Step 4
