Re: Overlays and encapsulations (was Re: Engineering discussions )

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 3/9/14, 8:07 PM, Alia Atlas wrote:
Joel,

On Sun, Mar 9, 2014 at 7:45 PM, Joel M. Halpern <jmh@xxxxxxxxxxxxxxx
<mailto:jmh@xxxxxxxxxxxxxxx>> wrote:
...

    While there are encapsulations whose primary purpose is adding
    additional information, most of the cases I can think of (MPLS,
    LISP, GRE, Mobile-IP) are cases where the primary purpose of the
    encapsualtion is to direct the traffic over a path that it might not
    otherwise chose or otherwise be able to traverse.


For MPLS, I think that the services, such as L3VPN, VPLS, pseudo-wires,
etc are hiding data from the underlay and conveying extra info.
  Arguably, so is LISP.

If you consider "frame format" extra information, then I guess Pseudowires carry extra information. But the primary point is to get the packet across the net.

At that point, you end up calling the tunnel endpoint identifier metadata instead of delivery information. Which seems to reduce the value of the distinction.

In the case of LISP, as specified, I don;t see that it carries extra packet information. It carries some tunnel maintenance information. When we add the LCAF in the resolution, we can get an implicit packet type. But even then the primary purpose of the encapsulation is to get the packet to the right place on the net. That is why it separates location (the outer destination) from identity (the inner destination).

Yours,
Joel


Regards,
Alia


    Yours,
    Joel







[Index of Archives]     [IETF Annoucements]     [IETF]     [IP Storage]     [Yosemite News]     [Linux SCTP]     [Linux Newbies]     [Fedora Users]