Re: New Internet Draft on automatic (end-user) tunneling for SSM

[Ross Finlayson <finlayson@live.com>]

At 02:07 AM 2/24/01, Dino Farinacci wrote:
> >>  From my understanding of GRE (please correct me if I'm wrong), the
> >> overhead to tunnel an arbitrary UDP multicast packet using GRE would 
> be 32
> >> bytes: 4 bytes (for the GRE header), plus 28 bytes (for the UDP/IP 
> headers
> >> of the encapsulated packet).
>
>     The overhead is an additional 24 bytes (20-byte fixed IP header and 
> 4-byte
>     GRE header).

But what about the UDP header of the packet that's being tunneled (i.e., 
the inner packet)?  That's another 8 bytes.  Wouldn't that go in the GRE 
packet as well?

         Ross.