On Tue, Sep 13, 2011 at 10:35:13AM -0400, Bill Roome wrote: > How many PIDs do we expect an ALTO server to handle? > > I ask because I've discovered that code that works fine with a few hundred > pids dies when I go to 5,000 pids. > > The biggest problem is the full cost map response message. With 5,000 > pids, that has 25 million cost entries.
I'm wondering whether retrieving the full N x N cost map is an important (or even a realistic?) use case. Consider an ALTO client embedded into a (P2P) application running on a PC connected to ISP A, say in PID 1. It makes sense to ask ISP A's ALTO server how expensive it is to get from PID 1 to candidate peers located in PIDs 2 (other access network of ISP A), 3 (ISP B) and 4 (ISP C), respectively. That is, it would need to know an 1 x N vector. But why should the application be interested in knowing the cost from PID 3 to 4? And even if it was interested, how would ISP A know the cost between ISP B and C's networks? If, on the other hand, we consider a big resource directory (e.g. P2P tracker) it would make sense to know the N x N matrix. But I doubt that there would be a single ALTO server that can deliver this matrix with a high level of detail. Who would be the operator of this ALTO server? I assume that the resource directory will have to ask several ALTO servers (of different ISPs) for their 1 x N matrix from their point of view and it will have to assemble the N x N matrix from that. Just my 2 cents. - Sebastian _______________________________________________ alto mailing list [email protected] https://www.ietf.org/mailman/listinfo/alto
