On Mon, Sep 26, 2011 at 7:39 AM, Bill Roome <[email protected]> wrote: > I have to agree with Sabastian. I think ALTO servers will be run by ISPs, > and will have high detail and accuracy for the endpoints the ISP runs. But > the detail and accuracy will drop as you get farther away from the ISP's > territory. > > Example: An ALTO server run by a US-based ISP might divide North America > into 100's of PIDs, and provide very accurate cost data between them. But > that ALTO might have only 2 PIDs for all of Japan. The server might give > good cost data for North America to those two Japanese PIDs, but it's cost > data between those two Japanese PIDs would be very flakey. > > An ALTO server run by a Japan-based ISP would be just the opposite: lots > of PIDs for Japan, but only a few for North America. >
Sure - and that's what I meant when I said "depending on what you mean by 'a high level of detail'". The RFC5632 shows one example of a "high level of detail" within a single ISP, and for that trial, much less granular costs were given to/from peering ISPs. The ISP maps were not consulted when determining costs between a pair of endpoints that were completely outside of the ISP. My only point was that the full map can still be useful. I'm not opposed to giving the ALTO Server a way of saying "I don't know", which as Sebastian pointed out, basically makes that a sparse matrix. However, that's a separate thread... Rich > - Bill Roome > > > On 09/24/2011 14:03, "Richard Alimi" <[email protected]> wrote: > >>> >>>But I doubt >>>that there would be a single ALTO server that can deliver this matrix >>>with a high level of detail. >> >>Why not? I think I would disagree with this, depending on what you >>mean by "a high level of detail". An ALTO Server does not need to >>reply based on information from within other ISPs. The semantics of >>ALTO maps and information in general is that it is from the ALTO >>service provider's perspective. > > > _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto
