Wow... amazon.com is completely disregarding the initial TCP congestion window: it looks like their servers simply pumping as much data as they can, with an aggressive retransmit timeout as well...

See wireshark capture below: no client ACK's have been sent following the initial GET request for the homepage, and Amazon servers are just pumping bytes: ~76KB outstanding, and growing! 

I guess that's one way to make your site faster... =/
Photo
Shared publiclyView activity