Re: DNS based Destination Selection

[marcelo bagnulo <marcelo@it.uc3m.es>]

Hi Iljitsch,

On Fri, 2003-06-20 at 00:21, Iljitsch van Beijnum wrote:
> On donderdag, jun 19, 2003, at 16:07 Europe/Amsterdam, Jay Ford wrote:
> 
> > The second of my two above points was that the remote end (which owns 
> > the
> > DNS) would be specifying the preferences of the sender of a packet.  
> > I'd
> > rather decide the preferences at my end for traffic I send.  Most net
> > interactions are bidirectional, so this is admittedly not a 
> > single-ended
> > problem, & the issue of who (sender or receiver) gets to decide path
> > selection for a packet borders on religious, so getting consensus on 
> > this
> > won't be easy.
> 
> This assumes that given the choice between two addresses for the other 
> end, choosing address #1 will make the packet flow over ISP A and 
> choosing address #2 will make the packet flow over ISP B. I see no 
> reason why this assumption would hold true in the majority of cases 
> today, and it certainly doesn't _necessarily_ hold true.
> 

If PA addressing is used, the selection of the dest address implies the
selection of the provider used to reach that destination address (at
least in steady state i.e. no failures). right?
If this is so, what case are you considering where the selection of the
dest addr does not implies the selection of the isp used to reach the
multi-homed site?

Regards, marcelo