Configure the Encapsulation Type

The encapsulation type you configure at each Layer 2 VPN site varies depending on which Layer 2 protocol you choose to configure. You need to use the same protocol at each Layer 2 VPN site if you configure ethernet-vlan as the encapsulation type. You do not need to use the same protocol at each Layer 2 VPN site if you configure any of the following encapsulation types:

• atm-aal5—ATM Adaptation Layer (AAL/5)
• atm-cell—ATM cell relay
• atm-cell-port-mode—ATM cell relay port promiscuous mode
• atm-cell-vc-mode—ATM virtual circuit (VC) cell relay non-promiscuous mode
• atm-cell-vp-mode—ATM virtual path (VP) cell relay promiscuous mode
• cisco-hdlc—Cisco Systems-compatible High-level Data Link Control (HDLC)
• ethernet—Ethernet
• ethernet-vlan—Ethernet VLAN
• frame-relay—Frame Relay
• interworking—Layer 2.5 interworking VPN
• ppp—Point-to-Point Protocol (PPP)

If you configure different protocols at your Layer 2 VPN sites, you need to configure a TCC encapsulation type. For more information, see Configure TCC Encapsulation on Interfaces.

Any Layer 2 VPNs configured with the atm-cell-port-mode, atm-cell-vc-mode, or atm-cell-vp-mode encapsulations on a router with JUNOS 5.6 later cannot interoperate with a router running JUNOS 5.5 or earlier.

To configure the Layer 2 protocol accepted by the PE router, specify the encapsulation type by including the encapsulation statement:

encapsulation type;

You can configure this statement at the following hierarchy levels:

• [edit logical-routers logical-router-name routing-instances routing-instance-name protocols l2vpn]
• [edit routing-instances routing-instance-name protocols l2vpn]