Re: [Int-area] Some thoughts on draft-yong-intarea-inter-sites-over-tunnels

[Joe Touch <[e-mail]>]

Fred,


On 12/9/2016 4:25 PM, Templin, Fred L wrote:
>
> Hi Joe,
>
>  
>
> I read your document and, for the applications I am concerned with, I
> still
>
> think what I am doing is the better approach. One thing that you may not
>
> have gathered is that the AERO interface does not maintain a
> replicated copy
>
> of the entire IP forwarding table;
>
I wasn't assuming it did - therein lies the problem.

> it only keeps neighbor cache entries for its
>
> currently active sets of neighbors. For AERO Clients, this would
> include the
>
> default router(s) and any peers that it has recently received
> Redirects from.
>
> For AERO Servers, the neighbor cache would include entries for the current
>
> list of associated Clients. So, the AERO interface is not a full-blown
> IP router;
>
> it is a neighbor discovery engine for its active set of neighbors.
>

But it would need to have the full-blown IP forwarding capabilities to
determine which next IP address is intended for a given packet handed to
it by the master IP forwarding table.

>  So, unlike a dynamic routing protocol the AERO interface uses IPv6
> Neighbor
>
> Unreachability Detection (NUD) instead of routing protocol keepalives to
>
> maintain reachability. There is also no routing protocol control messaging
>
> going out over the underlying data links – it is simply data packets plus
>
> occasional NUD messages.
>
That only describes how the table is populated. There's the further
issue of how the table is indexed, which is a full-blown forwarding
lookup (with policy information as well).

>  I noticed that your document was from 1997, which is the same year I
>
> started with SRI International. I think that was right around the time
>
> you and I first met.
>

Not sure - it was presented in early 1997 at the GBN workshop at
Infocom, but also at a few DARPA PI meetings before.

FWIW, I didn't think we met until the IETF, which was in Dec in DC that
same year.

Joe