Re: [DNA] Confirming today's face-to-face meeting decisions

[Erik Nordmark <erik.nordmark@sun.com>]

Brett Pentland wrote:

> There may be extra cost in making all the routers on a link agree on
> a "link scoped identifier", but that is an out of band management cost.
> Using "does this landmark still exist" has a cost during movement in
> that there is no negative acknowledgement and we have to wait for a
> timer to expire if the link is new and the landmark does not still
> exist.

While the timeout is the case in the current rrd draft, it isn't a 
fundamental property of landmark-based schemes.

For instance, in a landmark scheme the routers on the link can share the 
landmarks they have so that any router can respond. If you do this, a RS 
containing a landmark can be responded by any router, whether on the 
same link or not. If on the same link the router would respond "yes, 
this landmark is on this link" and if its it a different link the router 
would respond "no".

    Erik