On 1/27/2014 10:48 AM, joel jaeggli wrote:
On 1/27/14, 8:48 AM, Joe Touch wrote:
Those same mechanisms have provided hardware checksum support for a very long
time.
The new header and the payload are actually in different parts of the
forwarding complex until they hit the output queue, you can't checksum
data you don't have.
You can (and some do) the checksum component parts when things go into
memory; the partial sums can be added as the parts are combined in the
output queue.
I appreciate that we're all taking about what might be done, but the
reality is that there are many 'transparent TCP proxies' that have to do
this, so there's clearly a solution, and it clearly runs fast enough.
Joe