Long-haul 100Mbps EPL circuit throughput issue

Pablo Lucena plucena at coopergeneral.com
Fri Nov 6 05:17:26 UTC 2015

> Modern TCPs support and typically use window scaling (RFC 1323). You
> may not notice it in packet dumps because the window scaling option is
> negotiated once for the connection, not repeated in every packet.
Absolutely. Most host OS should support this by now. Some test utilities
however, like iperf (at least the versions I've used) default to a 16 bit
window size though.

The goal of my response was to allude to the fact that TCP relies on
windowing unlike UDP, thus explaining the discrepancies.

This is a good article outlining these details:


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