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Date: Mon, 5 Jan 2015 21:30:27 -0800
From: Matthew Hall <mhall@mhcomputing.net>
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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Subject: Re: [dpdk-dev] IPv6 Offload Capabilities
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On Mon, Jan 05, 2015 at 09:25:37PM -0800, Matthew Hall wrote:
> The same computation algorithm must be reused to calculate the IPV6 
> Pseudoheader checksum when generating ICMPV6, UDPV6, and other L4 protocols 
> whose definitions were retroactively modified to include the IPV6 
> pseudoheader, that happen to use the same checksum in L4 which IP used in L3.

To clarify, this is the part of the RFC which mentions it:

https://tools.ietf.org/html/rfc2460#section-8.1

Also, somebody else mentioned using TSO (TCP Segmentation Offload).

I did look at it but since it only seemed to work in TCP if I read everything 
right, that'd mean I had inconsistent code for IPv4 versus IPv6 stack, and 
inconsistent behavior for TCP from that for ICMP and UDP.

I was trying to avoid writing too much of this messy code if possible.

Matthew.