Subject: [alto] Starting up discussions on query/response requirements

From: "Das, Saumitra" <[email-masked]>
Date: Fri, 23 Jan 2009 17:34:02 -0800

Hi all,

 With an aim towards starting a discussion on the mailing list, it may be useful to discuss requirements for the query response feature of the ALTO service. My take on this is that it could have the following goals (this follows on from some of what I presented and the discussions with others at Minn)

1. The query should allow the client to express interest in one or more metrics that the ALTO service being queried supports
2. The ALTO service should be able to respond with a peer selection corresponding to the query annotated with metric values for peers
3. The query/response format should be general enough to accommodate the interests of many different kind of ALTO service providers from an ISP-friendly peer selection to a latency optimizing peer selection to a path disjointness optimizing peer selection.

Supporting (1) could require that we have a way for a client to contact an ALTO service and retrieve a set of metrics that are supported (these metrics could be pDistance, RTT, bw or something else that is ALTO service-specific) prior to the actual ALTO query.

In addition, we have to think about whether and how a client is allowed to express some function of the metrics in the query to the ALTO service such as: a peer selection in which a client asks the ALTO service to provide a peer selection that satifies all peers >128Kbps and ordered by latency. Or a peer selection in which a client asks for a peer selection/ranking that minimizes ISP costs annotated with average turnaround time. 

The current P4P interface first requires the client to place itself in the context of the ALTO service provider by the getPID interface. We should also think about something more general that allows the ALTO service to provide or obtain context about the client prior to servicing ALTO client queries. The context could be different for different types of ALTO service providers.

Thoughts?

-Saumitra

www.saumitra.info 

_______________________________________________
alto mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/alto