Subject: [CDNi] Service Access/Anchor Point Based Footprint/Capability advertisement

From: "Y. Richard Yang" <[email-masked]>
Date: Tue, 31 Jul 2012 05:04:58 +0800

Hi all,

It was suggested that I post this draft to the broader general list to 
get feedback:
http://www.ietf.org/internet-drafts/draft-yang-cdni-rr-foot-cap-00.txt

The objective of introducing service access (or anchor) point (SAP) 
based advertisement is to address the following issues in (asynchronous) 
footrptint/capability advertisement:

- allow advertisement to provide shortcut in the advertisement;

- allow multiple paths to the same End User (IP) to be advertised and 
*used*;

- allow flexible advertisements of different levels of quality of 
services to be advertised.

The SAP approach can be considered as a flexible mechanism to encode 
both resource centric advertisement, end-user QoE/performance centric 
advertisement, or a combination. For example, service access points 
(e.g., DNS load balancer address, cluster VIP, http load balancer, each 
represents a cluster of resources) provide an encoding of resources. On 
the other hand, if only one single high level service access point is 
provided, and the QoE table indicates QoE/servicability, then it is an 
end-user centric encoding.

The proposal does not specify specific QoE attributes (e.g., latency, 
bandwidth, frame loss rate at a given streaming rate) that will be 
advertised. There is a good on-going discussion on the semantics in the 
Footprint/Capability design team. This is, in particular, related with 
business models of CDNi. Jon/Stefano/Jan will provide a summary 
tomorrow. The discussion on what to advertise (or not to advertise) may 
have an impact on the proposed information base structure, but hopefully 
the information structure is robust and flexible to handle the outcome.

Any feedback/comments, in particular shortcomings of the proposal, will 
be greatly appreciated, as I do not run a CDN and hence the thinking is 
totally second hand.

Thanks!

Richard