[Sis-csi] IP Header Compression

[Wesley Eddy]

On Fri, Sep 09, 2005 at 07:59:51AM -0400, Howard Weiss wrote:
> Or isn't seen because those bits were missed or clobbered.


Any of the other bits (ports, options, protocol ids) that were mentioned
could get missed or clobbered too, so I don't see how that's relevant.
The difference that actually makes the IP identification more robust is
that there aren't things that change it in-transit like there are with
all of those other fields (on the "real" Internet at least).

 
> Scott,Keith L. wrote:
> 
> >Until that ipid happened to show up in somebody's data stream!


How does it show up in the data stream?  It's used for fragment
reassembly and is chosen at the liberty of the sending host.  So as long
as senders know that certain IDs are set aside for emergency commands,
there's no real problem.  The only issue is when senders that don't know
accidentally pick one of the IDs (1/2^16 chance per ID set aside), but
this is easily mitigated by also restricting the valid source address
field values for such commands.

-Wes

-- 
Wesley M. Eddy
Verizon FNS / NASA GRC
http://roland.grc.nasa.gov/~weddy
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