Configure Tunnel Interfaces
By encapsulating arbitrary packets inside a transport protocol, tunneling provides a private, secure path through an otherwise public network. Tunnels connect discontinuous subnetworks and enable encryption interfaces, virtual private networks (VPNs), and Multiprotocol Label Switching (MPLS). If you have a Tunnel PIC installed in your router, you can configure unicast and multicast tunnels.
You can configure two types of tunnels for VPNs: one to facilitate routing table lookups and another to facilitate VPN routing and forwarding instance (VRF) table lookups.
For information about encryption interfaces, see Configure Encryption Interfaces and the JUNOS Internet Software Configuration Guide: Getting Started. For information about VPNs, see the JUNOS Internet Software Configuration Guide: VPNs. For information about MPLS, see the JUNOS Internet Software Configuration Guide: MPLS Applications.
The JUNOS software supports the following tunnel encapsulations:
- Generic route encapsulation (GRE)
- IP over IP (IP-IP)
- Virtual Private Network (VPN)
- PIM encapsulation
This chapter discusses the following tunnel interface configuration tasks:
- Configure a Unicast Tunnel
- Configure a Multicast Tunnel
- Configure a Tunnel Interface for Routing Table Lookup
- Configure a Tunnel Interface for VRF Table Lookup
- Configure PIM Tunnels
- Configure an IPv6-over-IPv4 Tunnel
For examples of tunnel interface configuration, see the following sections: