Reply by rich...@gmail.com●January 9, 20082008-01-09
On Jan 9, 11:58=A0am, Michael Schuster <schusterSoc...@enertex.de>
wrote:
> Hi,
> just a silly Q we are discussing here. The CRC calculation for TCP-IP
> Protcols: Where is it calculated? In the CPU or the network-card?
Can be either, depending on the "checksum offload" setting of the
driver. Some NICs may not support checksum offload, but these now
seem to be in the minority.
>
> Thanks
> Michael
> --
> Remove the sport from my address to obtain emailwww.enertex.de- Innovative=
Systeml=F6sungen der Energie- und Elektrotechnik
Reply by Arlet Ottens●January 9, 20082008-01-09
Michael Schuster wrote:
> Hi,
> just a silly Q we are discussing here. The CRC calculation for TCP-IP
> Protcols: Where is it calculated? In the CPU or the network-card?
>
> Thanks
> Michael
TCP/IP doesn't use CRC (Cyclic Redundancy Check), but a much easier to
calculate 1's complement checksum. It is often calculated by the CPU,
although there are also network cards that can do it. On common
architectures, the calculation takes < 1 cycle/byte.
The Ethernet level CRC-32 is (nearly) always done by the netword card.
Reply by Michael Schuster●January 9, 20082008-01-09
Hi,
just a silly Q we are discussing here. The CRC calculation for TCP-IP
Protcols: Where is it calculated? In the CPU or the network-card?
Thanks
Michael
--
Remove the sport from my address to obtain email
www.enertex.de - Innovative Systeml�sungen der Energie- und Elektrotechnik