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Re: [Sigtran] Clarify SCTP max packet size.



Michael,

I believe I was correcting your statement.

--brian

Michael Tüxen wrote:                                 (Wed, 08 Jul 2009 00:43:33)
> Hi Brian,
> 
> sorry, I do not understand what you want to say...
> 
> Best regards
> Michael
> 
> On Jul 7, 2009, at 8:02 PM, Brian F. G. Bidulock wrote:
> 
> >Michael,
> >
> >Err, the MTU SCTP uses when bundling is the Association Path MTU.  It
> >subtracts IP header and SCTP header sizes from this Path MTU only when
> >considering how many chunks can be bundled.
> >
> >--brian
> >
> >Michael Tüxen wrote:                        (Tue, 07 Jul 2009  
> >18:51:09)
> >>On Jul 7, 2009, at 8:50 AM, <pierre.allegret at orange-ftgroup.com>
> >><pierre.allegret at orange-ftgroup.com > wrote:
> >>
> >>>Dear all,
> >>>
> >>>Just to add with the SCTP bundling feature. If the "SCTP MTU" is
> >>>1500, and the system is bundling messages at the SCTP level, you
> >>>should have the risk to segment at the IP level (because of the IP
> >>>header). So it is not efficient
> >>The MTU SCTP uses is the link layer MTU minus the headers for IP and
> >>SCTP.
> >>I have not seen an implementation which bundles at the SCTP layer and
> >>than
> >>needs to fragment at the IP layer. I would consider this broken...
> >>>to bundle sctp messages and to segment them at the IP level. Some
> >>>vendors limits "SCTP MTU" to avoid that. This is only the Maximum
> >>>transmission unit. If one SCTP message to transmit is greater, they
> >>>will segment it.
> >>>
> >
> >-- 
> >Brian F. G. Bidulock
> >bidulock at openss7.org
> >http://www.openss7.org/
> >
> 

-- 
Brian F. G. Bidulock
bidulock at openss7.org
http://www.openss7.org/