Re: Sub/Not Security, Presence service identifiers

"Peterson, Jon" <[email protected]> writes:

> Was there some reason that a wrapper seemed more attractive? Especially
> considering that a <timestamp> element is defined in PIDF? 

This is a follow up to my last note on timestamps.

If you look at the 05 draft of the PIDF document, it is clear the
<timestamp> element is an inapproprate replacement for the timestamp
in the wrapper I proposed.  The wrapper's timestamp records the time
at which a notification request was initiated.  A watcher uses this
information to make sure the information in the request was extracted
from the presence service's database in a timely fashion.  You use it
the same way you use the timestamp in an instant message.

The <timestamp> element in PIDF appears to serve a different purpose.
Here as a quote:

   (b) The presence format should be able to contain the timestamp of
       the creation of the PRESENCE INFORMATION.  The timestamp in the
       presence document lets the receiver know the time of the creation
       of the data even if the message containing it arrives late for
       some reason.  It can also be used to detect a replay attack,
       independent of the underlying signature mechanism.

In other words, it records the last time the presence information
changed.  In summary, the <timestamp> element cannot replace the
timestamp in the wrapper I proposed, but you could add another
element, such as <servedate> to replace the instant messaging like
syntax in the wrapper.

John




  [reminder: [email protected] for non-technical discussions, please]