RE: Last Call: Textual Conventions for IPv6 Flow Label to Pro posed Standard

[Pekka Savola <pekkas@netcore.fi>]

On Tue, 8 Apr 2003, Wijnen, Bert (Bert) wrote:
> > > > implementation laziness (just report -1 with everything for read access).  
> > > > This might be different if you were aiming towards R/W 
> > > > access.. which in turn might be a bad idea.
> > > > 
> > >
> > > They are indded max-access READ-WRITE or READ-CREATE.
> > > I do not see the problem with that either. Pls explain.
> > 
> > The problem of READ-WRITE or READ-CREATE seems to be that the MIB object
> > cannot exist before a connection has been established.  But then it
> > already has a flow label (or none) associated to it.  It seems too late to
> > change it on the fly.
> > 
> > So, being able to change flow labels of existing flows seems like 
> > something you must be very, very careful about in any case.
> > 
> > Hope this clarifies my concern.
> >  
> Somewhat... but why don't you take a look at RFC3289 and RFC3318 and
> tell me if you see anything wrong. (not that they may be speaking
> of FlowID instead of FlowLabel... but they mean the same thing).
> 
> I think that both RFCs are OK. Bot allow for writable/creatable objects
> and I think in the way they use it it is OK.
> I can see that there mightbe other uses that are not OK, but that of
> course needs to be evaluated on a case by case basis, which the
> MIB developers and later MIB doctors all do (or so I assume).

These two RFC's seem to be OK (from what little I understand MIB's): they
seem to define a way to specify which can be used to match the flow label
(e.g. in a diffserv classifier).   Being able to create such is of course 
OK.

What I was very worried about is creating e.g. an IPV6-MIB which includes
the list of ongoing sessions (compare to 'netstat -an' in a unix box) with
their flow labels -- and having R/W access to *modify* those flow labels.

That would be *bad*. :-)

This should clarify the distinction I was looking for.
 
-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings