GRE Tunneling for IPv6 is based on RFC2473?

[szhongling]

Is GRE tunneling technique for IPv6 based on RFC2473 or Cisco proprietary standard?

[Peter Paluch]

Hello Shi,

If using GRE over IPv6 (tunnel mode gre ipv6) then the encapsulation is done using the GRE encapsulating protocol as described in the RFC 2784. The outer IPv6 header will contain the value 0x2F (GRE) in its Next Header field, then the usual GRE header will follow, and the encapsulated datagram will be placed after the GRE header.

If you want to perform IPv6 tunelling per RFC2473, you need to configure the tunnel using the command tunnel mode ipv6

Best regards,

Peter

[szhongling]

Thank you so much!