Re: Preserving established communications (was RE: about draft-nordmark-multi6-noid-00)

["Spencer Dawkins" <spencer@mcsr-labs.org>]

This is actually a pretty helpful discussion. A couple of points...

Spencer


> Moving forward:
>
> The routing system has a limited response time that may not be
suitable for
> some apps. agree?

Agreed, but I'm not sure everyone else in the IETF agrees. It Would Be
Lovely to pick a target (TCP survivability, HTTP survivability, VoIP
survivability being three rough possibilities) and agree on it.

> Now what does the shim layer in A does?
> It can change the Source locator and/or the destination locator.
> Changing the source locator is not very useful since it will be
rewritten by
> the border router, and perhaps changing only the destination locator
doesn't
> solve the problem
> Perhaps if the rewrite ok bit is not set, this would mean that the
packets
> has to be routed through the isp that is compatible with the source
address
> contained in the packet, so that the host can force the isp
selection.

And it seems to me that the extent to which this happens has a
profound effect on mobile/multihomed applications and users in the
coming years.

I was the one standing up in the IAB workshop saying (I am
summarizing) if we get a lot of applications that WANT to handle their
own path selection, while we "solve the multihoming problem", they'll
STILL WANT to handle their own path selection after we "solve the
multihoming problem". If we pick a target (see previous), we can at
least tell some applications developers that they can ignore path
selection (multihoming happens automatically for them).

Spencer