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

Stewart Bryant <stbryant@cisco.com> Fri, 02 May 2014 10:15 UTC

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Date: Fri, 02 May 2014 11:15:46 +0100
From: Stewart Bryant <stbryant@cisco.com>
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Subject: Re: [Tofoo] VXLAN (UDP tunnel protocols) and non-zero checksums
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On 01/05/2014 04:14, Tom Herbert wrote:
>
>
> Assuming we are using Ethernet (I don't believe this can be a 
> requirement either) this only provides hop to hop protection, not end 
> to end. I don't have a completely error free network and checksum 
> errors while low, are non-zero.

Interesting, for years I have been looking for someone to put forward
some statistics on the error rate in a modern network, to get some
hard data on the UDP c/s issue. What error rate are you seeing?

Also can you help me understand what class of switch/router you are
seeing this on: h/w forwarding, s/w forwarding, host basted s/w 
forwarding... If you know whether the packet memory has any form of 
error detection/protection that would also be interesting.

Thanks

Stewart