Supported Standards for GRE and IP-IP Interfaces

The JUNOS software substantially supports the following generic routing encapsulation (GRE) and IP-IP standards:

RFC 1701, Generic Routing Encapsulation (GRE)
RFC 1702, Generic Routing Encapsulation over IPv4 networks
RFC 2003, IP Encapsulation within IP
RFC 2547, BGP/MPLS VPNs (over GRE tunnels)
RFC 2784, Generic Routing Encapsulation (GRE)
RFC 2890, Key and Sequence Number Extensions to GRE. The JUNOS software supports the key field, but not the sequence number field.