On 12-apr-2007, at 18:07, Saku Ytti wrote:
I agree. The throughput gains are small. You're talking about a
difference between a 4% header overhead versus a 1% header overhead
(for TCP).
6% including ethernet overhead and assuming the very common TCP
timestamp option.
Out of curiosity how is this calculated?
8 bytes preamble
14 bytes ethernet II header
20 bytes IP header
20 bytes TCP header
12 bytes timestamp option
4 bytes FCS/CRC
12 bytes equivalent inter frame gap
90 bytes total overhead, 52 deducted from the ethernet payload, 38
added to it.
90 / (1500 - 52 = 1448) * 100 = 6.21
90 / (9000 - 52 = 8948) * 100 = 1
Also note that the real overhead is much bigger because for every two
full size TCP packets an ACK is sent so that adds 90 bytes per 2 data
packets, or increases the overhead to 9% / 1.5%.
