# Configuring S-VLANs over Bridged Ethernet

S-VLANs over bridged Ethernet support the same set of higher-level protocols as VLANs over bridged Ethernet. You configure S-VLANs over bridged Ethernet in the same way that you configure VLANs over bridged Ethernet, with the addition of certain commands.

Like VLANs, configuring S-VLANs over bridged Ethernet interfaces consists of two basic tasks:

1. Configure the layers up to and including the S-VLAN subinterface.
2. Configure the higher-level protocols above the S-VLAN subinterface.

Before you can remove an S-VLAN subinterface, you must remove the upper-layer interface stack.

| Note: S-VLAN oversubscription is not supported on bridged Ethernet interfaces. For more information about specifying ATM interfaces and subinterfaces, see Interface Types and Specifiers in JunosE Command Reference Guide.

## Configuring S-VLAN Subinterfaces over Bridged Ethernet

To configure an S-VLAN subinterface over bridged Ethernet:

1. Create an ATM 1483 subinterface and associated PVC.
   host1(config)#interface atm 3/1.1 host1(config-subif)#atm pvc 1 5 33 aal5snap 0 0 0
2. Specify bridged Ethernet as the encapsulation method for the ATM 1483 subinterface.
   host1(config-subif)#encapsulation bridge1483
3. Create a VLAN major interface by specifying VLAN as the encapsulation method for the bridged Ethernet interface.
   host1(config-subif)#encapsulation vlan
4. Create a VLAN subinterface to carry the higher-level protocols by adding a subinterface number to the interface identification command.
   host1(config-subif)#interface atm 3/1.1.1
5. Assign an S-VLAN ID and a VLAN ID for the subinterface.
   host1(config-subif)#svlan id 4 255
6. Assign an S-VLAN Ethertype.
   host1(config-subif)#svlan ethertype 9200

Proceed to Configuring Higher-Level Protocols over S-VLANs for information about configuring higher-level protocols over the S-VLAN subinterfaces.

svlan ethertype

- Use to assign an Ethertype value for the S-VLAN subinterface.
- Choose one of the following Ethertype values:
  - 8100—Specifies Ethertype value 0x8100, as defined in IEEE Standard 802.1q
  - 9100—Specifies Ethertype value 0x9100, which is the default
  - 9200—Specifies Ethertype value 0x9200
- Use an Ethertype value that matches the Ethertype value set on the customer premises equipment (CPE) to which your router connects.
- Example
  host1(config-if)#svlan ethertype 8100
- Use the no version to restore the default value, 9100.
- See svlan ethertype.

svlan id

- Use to assign S-VLAN IDs and VLAN IDs to VLAN subinterfaces.
- Use S-VLAN ID and VLAN ID numbers that are in the range 0–4095 and that are unique within the Ethernet interface.
- Issue the svlan id command before any upper bindings are made, such as IP or PPPoE.
- Example
  host1(config-if)#svlan id 4 255
- There is no no version.
- See svlan id.

## Configuring Higher-Level Protocols over S-VLANs

The procedures for configuring IP, PPPoE, and MPLS protocols over S-VLANs on bridged Ethernet interfaces are identical to the procedures for configuring these protocols over VLANs on bridged Ethernet interfaces.

This section provides an example for configuring PPPoE interfaces over S-VLAN subinterfaces configured on bridged Ethernet. For descriptions of the commands used in this procedure, see Configuring Higher-Level Protocols over VLANs.

To configure PPPoE over S-VLAN over a bridged Ethernet interface:

1. Follow the steps in Configuring S-VLAN Subinterfaces over Bridged Ethernet to configure the S-VLAN subinterface.
2. Create a PPPoE major interface on the S-VLAN subinterface.
   host1(config-subif)#pppoe
3. Exit the subinterface context.
   host1(config-subif)#exit
4. Create a PPPoE subinterface by adding a subinterface number to the interface identification command.
   host1(config)#pppoe subinterface atm 3/1.1.1.1
5. Specify PPP as the encapsulation method on the interface.
   host1(config-subif)#encapsulation ppp
6. Assign an IP address and mask to the interface.
   host1(config-subif)#ip address 10.1.2.3 255.255.255.255