Re: [Bug-wget] Support for long-haul high-bandwidth links

[Daniel Stenberg]

On Thu, 1 Dec 2011, Andrew Daviel wrote:

> > First off, this early conclusion is incorrect. RTT has basically no impact 
> > on an ongoing TCP transfer these days since they introduced large windows 
> > for like a decade ago.
>
> I may be wrong, but I thought that to get significant benefit large windows 
> had to be enabled on every router between the source and destination, which 
> I did not think was the case on the public Internet.

Not exactly, but in firewalls and NATs or whatever you have in between. It is 
a TCP option, not IP: http://en.wikipedia.org/wiki/TCP_window_scale_option

I don't believe this specific option is a common problem these days as current 
network speeds over a single TCP connection wouldn't be achievable without it.

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 / daniel.haxx.se