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&#4294967295;sungen der Energie- und Elektrotechnik