Date: Tue, 10 Sep 2013 11:28:53 -0400
From: Julien Desfossez <[email protected]>

> > -----Message d'origine-----
> > The live trace reading mechanism offers guarantees that the viewer can 
> > never be in a position where it has to assume that it can read the trace 
> > safely. 
> > ------------------------------
>
> There are two risks when reading an active trace : reading a trace without 
> the complete metadata, and assuming a stream is inactive.
>
> If the viewer tries to read a trace for which it does not have the full 
> metadata (which is not known during normal tracing), it risks to crash 
> reading the trace. The live trace reading
> feature prevents the viewer from getting trace packets if there is new 
> metadata appended between two packets read.
>
> Also, if a stream is inactive, usually the viewer would have to wait until it 
> is active again to continue processing the trace. The live trace reading 
> feature informs the viewer that it can
> safely consider a stream inactive up to a certain point in time. That way, it 
> can continue to process the trace without waiting indefinitely for an 
> inactive stream. The live-timer
> parameter, configured during the session creation by the user, defines the 
> sending rate of these inactivity beacons.
>
> I hope it clarifies the situation.
>
> Julien

   Then maybe what should have been said is:

The live trace reading mechanism offers guarantees that the viewer can never be 
in a position where it cannot read the trace safely.

   Right?

Daniel U. Thibault
Protection des systèmes et contremesures (PSC) | Systems Protection & 
Countermeasures (SPC)
Cyber sécurité pour les missions essentielles (CME) | Mission Critical Cyber 
Security (MCCS)
R & D pour la défense Canada - Valcartier (RDDC Valcartier) | Defence R&D 
Canada - Valcartier (DRDC Valcartier)
2459 route de la Bravoure
Québec QC  G3J 1X5
CANADA
Vox : (418) 844-4000 x4245
Fax : (418) 844-4538
NAC : 918V QSDJ <http://www.travelgis.com/map.asp?addr=918V%20QSDJ>
Gouvernement du Canada | Government of Canada
<http://www.valcartier.drdc-rddc.gc.ca/>

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