From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] net/gtp: Add udp source port generation
 according to flow hash
Date: Thu, 23 Feb 2017 12:54:01 -0500 (EST)
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From: Andreas Schultz <aschultz@tpip.net>
Date: Thu, 23 Feb 2017 18:19:16 +0100 (CET)

> When we are talking about the xmit path, then currently none of the
> receivers we are talking to is going to be Linux and we have no
> idea how they will behave nor do we have any influence on them. Do
> we really need to make assumptions about other vendors implementations?
> 
> Traces on live GRX networks show that about 90% of the SGSN/S-GW
> that would talk to us always use the default GTP-U port as source
> port. Some multi chassis GSN's seem to assign source port ranges to
> chassis, but that has nothing todo with DDOS protection.

This is exactly what other UDP tunnel implementations did before
flow separation was prevelant.

I don't see the point of any of this discussion discouraging the
enablement of proper flow separation.