Thanks much for your comments.

I've made changes to address the editorial issues you raised.   For your other 
comments, I respond below.

On Oct 5, 2011, at 12:39 PM, Wayne Franklin wrote:
> Section 5.2.3: Messages should probably be restricted to the room security 
> levels because the messages will be logged with the room messages.

Yes, the room's restrictions ought to apply.  This is the way we've implemented 
it.

> Section 5.3: Collaboration Gateway currently adds security markings to 
> <presence/> and <iq/>.  Any reason to make this prohibited in XEP-0258.

Regarding <presence/>, it's my view is that either a user is authorized or is 
not authorized for a presence subscription.  If you have the situation where a 
user is only authorized for a subset of stanzas associated with a presence 
subscription, you introduce a number of complexities and undesirable behavior 
at the subscribers.

Regarding <iq/>, they are okay to have in type=set iq stanzas, such as the 
pubsub item publish case given in the XEP.  But they are not appropriate in 
results or errors.  This is because if there's a label, then there's going to 
be an entity which filters by it.  And filtering results and errors is quite 
problematic.  So, entities answering iq's are simply assumed to generate 
content acceptable for entities its to be passed to.

> What about "portion markings"?

For those who never known what a portion marking is, here's a quick definition:

Portion markings/labels is used to indicate different sensitivities of portions 
of the content, whereas an overall marking/labels indicates the overall 
sensitivity of the content.

There's no support for portion marking for a number of reasons.  I don't see 
portion marking of a stanza as terrible useful given that most stanzas are self 
contained content elements.  And I don't see portion marking for live, dynamic 
conversations involving multiple content elements.  And portion marking 
introduces significant complexity in both enforcing entities (e.g., servers) 
and producers and consumers.

> In Collaboration Gateway, we have secruity banners "UNCLASSIFIED/FOUO" and 
> portion markings "U/FOUO".

From what I could tell from reading the CDCIE CPP spec, CDCIE CPP provides a 
long display marking and a short display marking, the latter produced in a 
manner consistent with markings used for portion marking, is contained in an 
attribute which indicates it a portion marking, but that it always labeling the 
same content as the security banner provided in the security banner attribute.  

> We use the full security banner for the room classification and the portion 
> marking for individual chat messages.

Is there really portion marking going on?   Is there any text in the CDCIE CPP 
which indicates the scope of either of the marking is greater than or less than 
the stanza?  It seems to me that CDCIE is providing two markings it its label 
and asking clients display both.  That, by itself, doesn't see like portion 
marking to me.

I don't see a particular need for two display markings per label for prominent 
display with the labeled content.  I can see the need for markings for other 
purposes, such as in operator selection of labels.  That need was fulfilled by 
the introduction of selectors in the catalog.

> ColorCSS should not be used because some of the colors (like fuscia and aqua) 
> are subjective.

What aspects of the semantics of the color names is subjective?

> What security labels are applied to error messages?  

None.  For operational reasons, errors generally need to be passed along.  
Discarding them would be quite problematic.

For this reason, error messages should not contain sensitivity content.  (If 
the content is so sensitivity that the error can be delivered, the stream it 
came in ought to be closed with a stream error.)

> What about history messages?  "The server MUST only deliver messages to 
> participants for which they are cleared to receive."  -- may apply

Yes.  History messages should be filtered (and are in M-Link).  I'll add a note 
about that to the spec.

> 
> Does the XEP say anything about  Mr Unclassified  entering a secret room and 
> tagging a message as SECRET (even though he doesn't know anything secret)?

What should happen here depends on the security model used.   In many models, 
attempts to generate a message for which would the generating entity is not 
cleared to read would be denied (stanza rejected).  However, it's my 
understanding that some models allow for a user to generate for which they are 
not allowed to read.  One might have a clearance which separately grants read 
and write access.

The spec allows either model.  Our implementation denies submission of stanzas 
the submitter is not allowed to read.  (Our implementation is generally 
consistent with the SDN.801c model.)

-- Kurt

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