Narayanan, Vidya wrote:
Hi Vijay, I am not at all talking about reinventing what BitTorrent can do or even remotely about any actual p2p application itself. I am only talking about peer selection. However, I think there is a critical difference between what I view as contributing to peer selection and what the current proposed charter does.
Vidya: Thank you for your response. I think we are converging to the crucial difference in this thread. This is a good thing. More inline.
Peer selection is important to ISPs from a network utilization perspective and to peers themselves from a performance perspective. That automatically makes peer selection a function of multiple aspects - a) information that some service providers may decide to share with the peers, b) information that peers decide to make available about themselves to other peers for this purpose, and, c) any measurements peers may do on their own. The current charter definition (and from what I can tell based on your response below) only seems to allow for a). I would agree that c) is out of scope of ALTO and something that peers can additionally do. I strongly believe that b) should be part of the ALTO work.
I believe that incorporating (b) expands the charter quite a bit, whereas the consensus since the first BoF was for narrowing it down. I will also note that the feedback expressed on the list does not appear to view ALTO as a peer description protocol. To be sure, I am not unsympathetic to (b), it seems like a great problem to solve, it's just that ALTO may not be the best place to solve this problem. In the end, maybe the ADs can decide a way forward.
This functionality itself is application agnostic and requires an interoperable solution for it to be beneficial. This has nothing to do with content itself; it is purely about sharing information that helps with peer selection.
Protocols like BitTorrent already contain elements such that the peers know enough about other peers that the overlay is functioning. The information that BitTorrent (and other P2P overlays) do not have is topology and policies. This is where ALTO is urged to fill a crucial gap, at least initially. Since the IETF/MIT workshop, the problem outlined for what has become ALTO has been how to choose the peers wisely. We (i.e., the BoF/list participants) have been diligent to note that ALTO is not completely dependent on service providers; third parties can run ALTO servers as well; and these servers can use ad-hoc techniques like Ono (which was discussed yesterday on the list) or some form of Internet Coordinate Systems to derive a topology. We have also been diligent to note that ALTO is an additional service provided to an overlay; the overlay will continue to function without it (albeit in a bit of a sub-optimal manner.) We have also noted given a choice between a service provider run ALTO server and a third party ALTO server, that peers will naturally gravitate towards the ALTO server that provides them the best information over a long period of time. In other words, we have covered substantial grounds since the IETF/MIT workshop and the Dublin BoF based on the premise of the problem as the group has understood it. Thanks, - vijay -- Vijay K. Gurbani, Bell Laboratories, Alcatel-Lucent 1960 Lucent Lane, Rm. 9C-533, Naperville, Illinois 60566 (USA) Email: vkg@{alcatel-lucent.com,bell-labs.com,acm.org} WWW: http://www.alcatel-lucent.com/bell-labs _______________________________________________ Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf