Configuring a Logical Tunnel Interface

Logical tunnel (lt) interfaces provide quite different services depending on the host routing platform:

On M-series and T-series routing platforms, logical tunnel interfaces allow you to connect logical systems, virtual routers, or VPN instances. The router must be equipped with a Tunnel Services PIC or an Adaptive Services Module (only available on M7i routers). For more information on the latter applications, see the JUNOS VPNs Configuration Guide.
On J-series Services Routers, lt interfaces have a completely different function; they enable you to change class-of-service (CoS) classifications and header bits.

For more information, see the following sections: