Vyatta NOS documentation

Learn how to install, configure, and operate Vyatta Network Operating System (Vyatta NOS), which helps to drive our virtual networking and physical platforms portfolio.

Applications for GRE

You might use GRE in the following situations:

  • Connect networks that are running non-IP protocols, such as native LAN protocols, across the public IP network. Non-IP protocols, such as Novell IPX or Appletalk, are not routable across an IP network. A GRE tunnel allows you to create a virtual point-to-point link between two such networks over the public WAN.
  • Route IPv6 packets across an IPv4 network, or connect any two similar networks across an infrastructure that uses different IP addressing.
  • Encrypt multicast traffic. IPsec, which is a standard mechanism for providing security on IP networks, cannot encrypt multicast packets. However, multicast packets can be encapsulated within a GRE tunnel and then routed over a VPN connection, so that the encapsulated packets are protected by the IPsec tunnel.