Table of Contents

Configuring IP over ATM

This chapter describes how to configure IP over ATM on the ATM switch router. The primary use of IP over ATM is for inband management of the ATM switch router.

Note   This chapter provides advanced configuration instructions for the Catalyst 8540 MSR, Catalyst 8510 MSR, and LightStream 1010 ATM switch routers. For further information about Layer 3 protocols over ATM, refer to the Guide to ATM Technology. For complete descriptions of the commands mentioned in this chapter, refer to the ATM Switch Router Command Reference publication.

This chapter includes the following sections:

Configuring Classical IP over ATM

This section describes configuring a port on a ATM switch router to allow a classical IP-over-ATM connection to the ATM switch router's route processor and optional ATM router module.

The following sections describe configuring the ATM switch router for classical IP over ATM in either a switched virtual channel (SVC) or permanent virtual channel (PVC) environment.

Configuring Classical IP over ATM in an SVC Environment

This section describes classical IP over ATM in an SVC environment. It requires configuring only the device's own ATM address and that of a single ATM Address Resolution Protocol (ARP) server into each client device.

For a detailed description of the role and operation of the ATM ARP server, refer to the Guide to ATM Technology.

The ATM switch router can be configured as an ATM ARP client to work with any ATM ARP server conforming to RFC 1577. Alternatively, one of the ATM switch routers in a logical IP subnet (LIS) can be configured to act as the ATM ARP server itself. In that case, it automatically acts as a client as well. The following sections describe configuring the ATM switch router in an SVC environment as either an ATM ARP client or an ATM ARP server.

Configuring as an ATM ARP Client

In an SVC environment, configure the ATM ARP mechanism on the interface by performing the following steps, beginning in global configuration mode:

Note   The end system identifier (ESI) address form is preferred in that it automatically handles the advertising of the address. Use the network service access point (NSAP) form of the command when you need to define a full 20-byte unique address with a prefix unrelated to the network prefix on that interface. You only need to specify a static route when configuring an ARP client using an NSAP address.

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

NSAP Address Example

Figure 12-1 shows three ATM switch routers and a router connected using classical IP over ATM.

The following example shows how to configure the route processor interface ATM 0 of client A in Figure 12-1, using the NSAP address:

ESI Example

The following example shows how to configure route processor interface ATM 0 of client A in Figure 12-1 using the ESI:

Configuring as an ATM ARP Server

Cisco's implementation of the ATM ARP server supports a single, nonredundant server per LIS and one ATM ARP server per subinterface. Thus, a single ATM switch router can support multiple ARP servers by using multiple interfaces.

To configure the ATM ARP server, perform the following steps, beginning in global configuration mode:

Note   The ESI address form is preferred in that it automatically handles the advertising of the address. Use the NSAP form of the command when you need to define a full 20-byte unique address with a prefix unrelated to the network prefix on that interface. You only need to specify a static route when configuring an ARP server using an NSAP address.

The idle timer interval is the number of minutes a destination entry listed in the ATM ARP server ARP table can be idle before the server takes any action to timeout the entry.

Example

The following example configures the route processor interface ATM 0 as an ARP server (shown in Figure 12-1):

Displaying the IP-over-ATM Interface Configuration

To show the IP-over-ATM interface configuration, use the following EXEC commands:

Examples

In the following example, the show atm arp-server command displays the configuration of the interface ATM 0:

The following example displays the map-list configuration of the static map and IP-over-ATM interfaces:

Configuring Classical IP over ATM in a PVC Environment

This section describes how you configure classical IP over ATM in a permanent virtual channel (PVC) environment. The ATM Inverse ARP (InARP) mechanism is applicable to networks that use PVCs, where connections are established but the network addresses of the remote ends are not known. A server function is not used in this mode of operation.

In a PVC environment, configure the ATM InARP mechanism by performing the following steps, beginning in global configuration mode:

Repeat these tasks for each PVC you want to create.

The inarp minutes interval specifies how often Inverse ARP datagrams are sent on this virtual circuit. The default value is 15 minutes.

Note   The ATM ARP and ATM InARP mechanisms work with IP only. All other protocols require map-list command entries to operate.

Example

The following example shows how to configure an IP-over-ATM interface on interface ATM 0, using a PVC with AAL5SNAP encapsulation, inverse ARP set to ten minutes, VPI = 0, and VCI = 100:

Displaying the IP-over-ATM Interface Configuration

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

Example

The following example displays the map-list configuration of the static map and IP-over-ATM interfaces:

Mapping a Protocol Address to a PVC Using Static Map Lists

The ATM interface supports a static mapping scheme that identifies the ATM address of remote hosts or ATM switch routers. This IP address is specified as a permanent virtual channel (PVC) or as a network service access point (NSAP) address for switch virtual channel (SVC) operation.

The following sections describe configuring both PVC-based and SVC-based map lists on the ATM switch router. For a more detailed discussion of static map lists, refer to the Guide to ATM Technology.

Configurations for both PVC and SVC map lists are described in the following sections:

Configuring a PVC-Based Map List

This section describes how to map a PVC to an address, which is a required task if you are configuring a PVC.

You enter mapping commands as groups. You first create a map list and then associate it with an interface. Perform the following steps, beginning in global configuration mode:

You can create multiple map lists, but only one map list can be associated with an interface. Different map lists can be associated with different interfaces.

Example

Figure 12-2 illustrates a connection configured with a PVC map list.

The following example shows the commands used to configure the connection in Figure 12-2.

Displaying the Map-List Interface Configuration

To show the map-list interface configuration, use the following EXEC command:

Example

The following example displays the map-list configuration at interface ATM 0:

Configuring an SVC-Based Map List

This section describes how to map an SVC to an NSAP address. This is a required task if you are configuring an SVC.

You enter mapping commands as groups. You first create a map list and then associate it with an interface. Perform the following steps, beginning in global configuration mode:

You can create multiple map lists, but only one map list can be associated with an interface. Different map lists can be associated with different interfaces.

Examples

Figure 12-3 illustrates an SVC connection configured with a map list.

The following example shows the commands used to configure the connection in Figure 12-3:

Displaying the Map-List Interface Configuration

To show the map-list interface configuration, use the following EXEC command:

Example

The following example displays the map-list configuration at interface ATM 0: