* Re: SCTP PMTU calculation not accounting chunk padding.
@ 2015-09-09 20:39 Vlad Yasevich
0 siblings, 0 replies; only message in thread
From: Vlad Yasevich @ 2015-09-09 20:39 UTC (permalink / raw)
To: linux-sctp
On 09/09/2015 03:00 AM, Deepak Khandelwal wrote:
> Hi,
>
>
> It looks like the PMTU calculation in SCTP kernel / RFC, seems to be not
> accounting the chunk padding
>
>
> SCTP calculate the fragmentation point to fragment the packet.
>
>
>
> Frag_point = PMTU – (sctp header length + sctp chunk length) – IP header
> length
>
>
>
> After the frag_point, user data fragmentation happens at SCTP layer, but
> while sending packet due the need of chunk padding, data size still more
> then mtu of in between router, and packet doesn’t pass through to the
> channel . local SCPT stack always end up receiving the ICMP FRAG _NEEDED
> messages.
>
> I am using Kernel version 2.6.34.9-WR4.3
>
You are missing
commit c08751c851b78514f6ec5f77f7cbebaac63d15c0
Author: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Date: Mon Sep 2 15:58:25 2013 +0200
net: sctp: Fix data chunk fragmentation for MTU values which are not multiple of 4
-vlad
> Thanks !
> Best Regards,
> Deepak
>
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2015-09-09 20:39 UTC | newest]
Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-09-09 20:39 SCTP PMTU calculation not accounting chunk padding Vlad Yasevich
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).