Example: Configuring ATM, SONET, Loopback, and Out-of-Band Management Interfaces

The following example shows how to configure the interfaces on your router. It covers configurations for Asynchronous Transfer Mode (ATM), SONET, loopback, and out-of-band management interfaces.

The following example shows how to configure an ATM interface:

[edit]interfaces {at-4/0/0 {description core-router; atm-options {vpi 0 maximum-vcs 1024;ilmi;}unit 131 {description to-other-core-router;encapsulation atm-snap;point-to-point;vci 0.131;family inet {address 12.1.1.1/30;}family iso;}}}

The fxp0 interface can be used for out-of-band management. However, because most service providers use inband communication for management (because of lower operating costs), you can disable this interface to make the router more secure.

The following example shows how to configure an fxp0 interface as a loopback interface:

[edit]interfaces {fxp0 {disable;}}

The following example shows how to configure the loopback interface and apply a firewall filter to protect the Routing Engine. This filter, which you define at the [edit firewall] hierarchy level, checks all traffic destined for the Routing Engine that enters the router from the customer interfaces. Adding or modifying filters for every interface on the router is not necessary.

[edit]interfaces {lo0 {unit 0 {family inet {filter {input protect-routing-engine;}address 10.10.5.1/32;}family iso {address 48.0005.80dd.f900.0000.0001.0001.0000.0000.011.00;}}}}

The following example shows how to configure a SONET interface.

[edit]interfaces {so-2/0/0 {description To-other-router;clocking external;sonet-options {fcs 32;payload-scrambler;}unit 0 {family inet {address 10.1.5.1/30;}family iso;}}}