Re: Informal meeting on blind caching

[Richard Bradbury <[e-mail]>]

On 17/07/2016 18:03, Martin Thomson wrote:
> We are having a meeting on blind caching on Tuesday 08:30 in
> Charlottenburg I.  Folks who are interested are invited to join us.
>
> Rough agenda is to discuss what this is, the status of specs and
> implementations.  Then we are looking to get some input on the work
> that has been done and what might need to happen next.
>
> For those not familiar with this, the following drafts are recommended reading:
> https://tools.ietf.org/html/draft-thomson-http-scd
> https://tools.ietf.org/html/draft-thomson-http-bc
> https://tools.ietf.org/html/draft-reschke-http-oob-encoding
> https://tools.ietf.org/html/draft-thomson-http-mice
> https://tools.ietf.org/html/draft-ietf-httpbis-encryption-encoding

Hi. Thanks for an interesting session last week.

Based on my reading of the Internet Drafts I think these are the two 
main Use Cases under consideration here:

 1. *Blind caching in a CDN edge cache that is acting as a delegated
    origin server.*
      * Described in draft-thomson-http-scd.
      * Making use of the techniques described in
        draft-reschke-http-oob-encoding, draft-thomson-http-mice and
        draft-ietf-httpbis-encryption-encoding.
 2. *Blind caching in an explicitly configured proxy server.*
      * Described in draft-thomson-http-bc.
      * Making use of the techniques described in
        draft-reschke-http-oob-encoding, draft-thomson-http-mice and
        draft-ietf-httpbis-encryption-encoding.

The discussion in Berlin last Tuesday morning flowed fairly freely 
between the two Use Cases, so I just wanted to check my understanding. 
In particular, the I-D for the second Use Case doesn't have a sequence 
diagram, so I attach my best guess of how everything fits together and 
invite comments from the authors.

Finally, a basic question: For this to work, both the origin server and 
the proxy server need to support blind caching. So how does a User Agent 
discover whether both do? Through trial and error?


Regards,

-- 
Richard Bradbury | Lead Research Engineer
BBC Research & Development
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