Re: [Tofoo] VXLAN (UDP tunnel protocols) and non-zero checksums

Joe Touch <touch@isi.edu> Thu, 01 May 2014 20:21 UTC

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Date: Thu, 01 May 2014 13:20:53 -0700
From: Joe Touch <touch@isi.edu>
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Subject: Re: [Tofoo] VXLAN (UDP tunnel protocols) and non-zero checksums
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On 4/30/2014 2:23 PM, Behcet Sarikaya wrote:
> Here is what VXLAN says on tunneled traffic:
>
> Tunneled traffic over the IP network can be secured with traditional
>     security mechanisms like IPsec that authenticate and optionally
>     encrypt VXLAN traffic. This will, of course, need to be coupled with
>     an authentication infrastructure for authorized endpoints to obtain
>     and distribute credentials.
>
> Based on this, UDP checksum text seems to be consistent, no?

No; the UDP checksum is not for authetication. It is an error check.

The only party that can decide to make the UDP checksum optional when 
using IPv4 is the source - by inserting zero.

It's not the receiver's choice to ignore that checksum if it's not zero. 
That's where this doc breaks the current standards.

Joe