Configuring Layer 2.5 VPNs
Layer 2.5 VPNs are an extension to Layer 2 VPNs. The main difference is that Layer 2.5 VPNs are not required to have the same media on both ends of the connection. Layer 2.5 VPNs have the same capabilities as the CCC and Layer 2 VPN implementation in JUNOS 5.2 and later.
Layer 2.5 VPNs support the same media types as TCC: ATM, Cisco HDLC, Ethernet, Ethernet Extended VLAN, Frame Relay, and PPP. The only traffic type that is currently supported is IPv4. Also, IS-IS adjacencies cannot be formed across a TCC connection, because they use Open Systems Interconnection (OSI) framing.
To configure Layer 2.5 VPNs, complete the following tasks:
- Configure the Encapsulation on Interfaces Participating in the Layer 2.5 VPN
- Configure the Layer 2.5 VPN
To view an example of a Layer 2.5 VPN, go to the following sections: