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Re: Jumbo Frames?

On Wednesday 01 Feb 2006 08:29, mike wrote:
> ..... I could
> get anywhere from 100-117MB/sec. Which isn't a problem -
> theoretically, gigE can only give me 125MB/sec anyway... so
> 116-117MB/sec I think is really good, so I am happy now. :)

The figure you have is about right.  Yes there are 8 bits in a byte, so you'd 
expect 125MB; but because you're dealing with packets, and not a contiguous 
bit stream  {à la Spectrum cassette loading},  there are overheads -- every 
packet has to have a header and footer, which count against the total.

By using bigger packets, you will have fewer headers and footers -- and so 
improve the transmission rate.

BTW, RS232 serial comms  {old-fashioned modems!}  effectively uses one-byte 
"packets", with a 2-bit overhead.  This is why you have to divide by ten, not 
eight, when converting bits to bytes in serial comms.

delta echo bravo six four at earthshod dot co dot uk

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