RE: What is CONTENT?

[aaron@panamsat.com]

> The current (-02) draft of the model document includes a 
> formulation of
> CONTENT in terms of CONTENT DATA UNITs.  No-one on the design 
> team seems to
> like this approach very much. I am happy to replace these 
> definitions or
> eliminate them entirely, but I find the leading proposed replacement
> somewhat unsatisfactory.
> 
> Barron's suggestion is that CONTENT is a "typed finite 
> sequence of octets."
> While this is correct, it seems incomplete.

Isn't CONTENT actually APPLICATION DATA? It seems that what we are talking
about is stuff handled by some application. After all, this architecture
doesn't require a browser or player or even that the data be consumed by a
person. I agree that it's a bit of a clunky term. Perhaps APPLICATION DATA
OBJECT? Ugh, worse. :(

> 
> I think that we need to get across the following points:
> 
> 1. We are talking about digital content -- that which can be sensibly
> carried over IP. 

I'd go a little farther: it should be carried over an IETF Transport layer
service as well. Allowing non-standard transport services for peering CDNs
would seem....counter productive.

> 3. When resources are scarce, there is a fundamental tradeoff between
> accurate (bit-complete) delivery and timely delivery.  A CDN 
> can be asked to
> guarantee one or the other, but not both; when it is asked to 
> guarantee
> timely delivery, it must also be told what can be dropped, 
> and under what
> circumstances.  

This seems like a useful concept which might work well with DIFFSERV. 

--aaron

---

Aaron Falk
NET-36 Director, System Engineering
PanAmSat Corporation
*	Phone: 	203.905.8275
*	http://www.net-36.com