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Re: [alto] Info Resource Dirs, OPTIONS, 300 Multiple Choices and all that jazz ....

Richard Alimi <rich@velvetsea.net> Sat, 30 July 2011 15:05 UTC

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Subject: Re: [alto] Info Resource Dirs, OPTIONS, 300 Multiple Choices and all that jazz ....
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On Thu, Jul 28, 2011 at 11:56 AM, Bill Roome <w.roome@alcatel-lucent.com> wrote:
> So the directory server DOES have an authoritative list of uris -- because
> there is no other URI discovery mechanism! -- but it doesn't really know
> what services those URIs provide.

I'm confused.  The current mechanism supposes that a client knows
which service it wants.  The directory and HTTP responses let it
discover the correct URI for that service.

I don't think its ever the case that a client or server don't know
which service(s) a URI provides.  The server (which produces the
directory), and by extension the client (because it consumes the
directory) knows the set of services that a URI provides.  The HTTP
server / ALTO Server managing that particular URI gets to say whether
that URI directly provides that service, or whether some other URI
that it manages actually provides it (and it returns an HTTP status
code indicating which is true).

Or is there a different scenario you have in mind?

Rich

> That sounds truly bizarre to me. How
> could that happen?
>
> Okay, I know how that COULD happen -- idiotic configuration!
>
> But more precisely, could you explain why a well-designed designed ALTO
> server can give an authoritative list of URIs WITHOUT also knowing what
> services they provide?
>
>        - Bill Roome
>
>
> On 07/28/2011 14:16, "Thomson, Martin" <Martin.Thomson@commscope.com>
> wrote:
>
>>>
>>>I'd also suggest that the resource directory MUST be authoritative (at
>>>least within any Expires time).
>>
>>Sadly, that's not possible.  Even if the directory and the indicated
>>resource are on the same server, there is no guarantee.
>
>
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