Re: [alto] Adopting draft-kiesel-alto-xdom-disc as WG item?

[Sebastian Kiesel <[e-mail]>]

On Fri, Jul 15, 2016 at 02:00:07PM +0000, wang xin wrote:
> Dear all,
> 
> 
> For the first part, I think a key point is the cost(X, Y) should be
> kept at XDOM-DISC(X) or XDOM-DSIC(Y) or both. If only at XDOM-DISC(X),
> then it would become much complex for an ECS request like "give me all
> cost values with destination Y". It should ask all ALTO servers to get
> the result (here I assume cost(X, Y) != cost(Y, X)). It is the same
> for only at XDOM-DISC(Y). Hence, I think the cost(X, Y) should be kept
> at both servers.

Yes.  It should be kept at both servers.

However, we must be aware that if we ask for routingcost(X,Y) at the
server discovered by XDOM-DISC(X) we may get a different numerical
result than if we ask the same query at the server discovered by
XDOM-DISC(Y).  This is because of the (intentionally) vague definition
of routingcost as a relative measure without a "base unit".

Therefore, we need to figure out, which is the host that has choices
to which other hosts to talk.  The address of this host, who needs
the ALTO guidance, will be used as parameter for XDOM-DISC.

Sebastian