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SubjectRe: zero-copy TCP fileserving
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> Something like:
>
> (1) A checksum of zero means don't check the checksum.
> (2) You can't route a zero-checksum IP packet. If you route it,
> you must checksum it before routing.

LAN CRC's aren't sufficient. They protect card->card not host->host. And
the world _does_ see host->host errors. Also IP checksums are cheap, even
in silicon

> This would allow LANs to operate at higher speeds where a hardware CRC
> makes sure the data is good anyway, while maintaining compatibility

It would make no difference. The cost nowdays is the cost per packet big time.
Going to bigger packets is a huge win. The checksum helps but not that much.

There are also people researching using FPGA's to do hardware assisted
IP handling (eg hardware TCP demux)


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