W3C home > Mailing lists > Public > w3c-dist-auth@w3.org > October to December 2003

Re: Review of draft-ietf-webdav-quota-02.txt

From: Brian Korver <briank@xythos.com>
Date: Mon, 17 Nov 2003 14:23:30 -0600
Cc: w3c-dist-auth@w3.org
To: Stefan Eissing <stefan.eissing@greenbytes.de>
Message-Id: <E8A03FF4-193B-11D8-81A9-000393751598@xythos.com>

On Friday, November 14, 2003, at 04:27  AM, Stefan Eissing wrote:
> Brian,
>
> I put my mind into blank slate mode and read the draft 2 for the first 
> time.
>
> I think it is a big improvment from where we started from. One item I 
> found
> confusing though and that is the example for DAV:quota-assigned-bytes
> (and the mental model behind the example).

I agree on both counts.  Any help on making the example less confusing
would be appreciated.


>
> The draft seems to say that /A and /A/B have separate 
> DAV:quota-assigned-bytes
> properties, however they are in the same "set of collections" when the 
> value
> of DAV:quota-available-bytes/DAV:quota-used-bytes is computed.
>
> (See definition of "set" in the explanation to DAV:quota-used-bytes - 
> seems to
> be a copy from the NFS spec.)
>
> In NFS-Quota, the model seems to be simple: each quota applies to a set
> of collections/files and each member of this set would report the same
> quota properties.

I'm not sure that I understand what you're saying.  On BSD, for 
instance,
quota is specified per-filesystem.  Therefore, if I've got the 
following mount
points and quota specified:

     /home/briank/           # my home directory, quota 1GB
     /home/briank/mp3s       # quota 100GB
     /home/briank/video      # quota 50GB
     /home/briank/small      # quota .25GB

So here, the 'set' is a filesystem.


>
> In WebDAV-quota (draft-2): there is a separate quota for each 
> collection
> (e.g. the assigned-bytes), but available-/used-bytes are the same for
> resources in the same set.
>
> Two Problems come to my mind now:
> 1) If a collection of the "set" has the DAV:quota-assigned-bytes not
>   explicitly set, what value would it report? Say for /A/C, /A/B/D and
>   /E (all in the same set)?

I presume the server would just not return DAV:quota-assigned-bytes
if it isn't set.  Hmm, that should be stated in the document.  Will fix.


>
> 2) If a client wants to increase DAV:quota-available-bytes in a certain
>   collection, it has to increase the DAV:quota-assigned-bytes. But in
>   your example: increasing assigned-bytes on /A/B will not have any
>   effect on the DAV:quota-available-bytes. What is a generic client 
> supposed
>   to do then?

The generic client should allow the user to change quota wherever
it can be.  It is up to the user to understand the quota model.
I don't know what else can be done.

-brian
briank@xythos.com
Received on Monday, 17 November 2003 15:23:27 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 2 June 2009 18:44:05 GMT