Example: Configuring Dynamic Subscriber Interfaces over Bridged Ethernet

Requirements

• JunosE Release 7.1.0 or higher-numbered releases
• E Series router (ERX7xx models, ERX14xx models, the ERX310 router, the E120 router, or the E320 router)
• ASIC-based line modules that support Fast Ethernet or Gigabit Ethernet

Overview

Figure 1 shows the interface stack built for this configuration.

Figure 1: IP over Bridged Ethernet over ATM Dynamic Subscriber Interface Configuration

Configuring Dynamic Subscriber Interfaces over Bridged Ethernet

Step-by-Step Procedure

1. Configure the DHCP server.

   For instructions, see Configuring the DHCP Local Server .

2. Create an ATM major interface.
   host1(config)#interface atm 3/3
3. Create an ATM 1483 subinterface.
   host1(config-if)#interface atm 3/3.1
4. Configure an associated PVC for the ATM 1483 subinterface by specifying the VCD, the VPI, the VCI, and the encapsulation type.
   host1(config-subif)#atm pvc 10 100 22 aal5snap

   Specify the VCD, the VPI, the VCI, and the encapsulation type. (For more information about these parameters, see the Creating a Basic Configuration section in JunosE Link Layer Configuration Guide .)

   Use the no version to remove the specified PVC.

5. Specify bridged Ethernet as the encapsulation method on the ATM 1483 subinterface.
   host1(config-subif)#encapsulation bridge1483

   Use the no version to remove bridged Ethernet as the encapsulation method on the interface.

6. Create the primary IP interface by assigning an IP address and mask to the bridged Ethernet interface (or make it unnumbered).
   host1(config-subif)#ip address 192.168.2.20 255.255.255.0

   You must specify the layer 2 encapsulation before you set the IP address. Issuing this command creates the primary IP interface. You must create a primary IP interface on which to enable dynamic creation of subscriber interfaces.

   Use the no version to remove the IP address or to disable IP processing.

7. Configure the primary IP interface to enable dynamic creation of subscriber interfaces.
   host1(config-subif)#ip auto-configure ip-subscriber
8. (Optional) Append the virtual router name to the subscriber interface in case of DSI configuration.
   host1(config-if)#ip auto-configure append-virtual-router-name
9. (Optional) Specify the source address of traffic that is destined for the primary IP interface.
   host1(config-subif)#ip source-prefix 192.168.2.20 255.255.255.0

   You can use this command to configure a subscriber interface or a primary IP interface enabled for dynamic creation of subscriber interfaces to demultiplex traffic with the specified source address. Use the no version to remove the association between the interface and the specified IP source address and mask.