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Date: Thu, 2 Feb 2006 22:20:46 -0800 (PST)
From: kamal kc <kamal_ckk@yahoo.com>
To: freebsd <freebsd-net@freebsd.org>
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Subject: offloading ip checksum calculation to the NIC
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dear all,

i want to offload ip checksum calculation to the NIC.
I use 3Com 3c905B-TX NIC cards.

I found that there are variables::>>

        int	csum_flags;		/* flags regarding checksum */
	int	csum_data;		/* data field used by csum routines */

in struct pkthdr in mbuf.h.

also i found the various flags for the hardware checksumming.
but i don't know the exact steps i need to do 
in order to offload checksumming. 

should i set the csum_flags to CSUM_IP and point
csum_data to the start of the ip header ??

it would be a great help if anybody
could tell me what do i need to do ?

thanks,
kamal




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