Re: [tlug] What would happen to the Internet if the US fell off the map

["Josh Glover" <jmglov@example.com>]

On 04/08/07, Curt Sampson <cjs@example.com> wrote:

> Basically, if a link is running 10-20% packet loss, you might as well
> consider it dead, for all practical purposes.

You are unassailably right for applications that rely on one
connexion; ssh becomes completely unsustainable at right around 10%
(in The Real World, I've had this happen to me quite recently).

However, one lovely property of TCP/IP is that it enables bursty
applications to have a chance until packet loss approaches 50% (take a
moment to think about this; basically, as packet loss approaches and
surpasses 50%, the chances of any round-trip drop to 0% in a hurry).
e.g. in my recent experience with a link that was dropping between
6-26% of my packets ("ping -c 100 -q" was reporting 12% or
thereabouts, but lesser values of -c were showing lots of flux), ssh
was dead in the water, but my web browsing experience was degraded so
little that it took my 30 minutes to notice, "hey, the 'Net is slow
today!"

Pretty awesome, and that awesomeness is not an accident. TCP/IP was
designed to operate in these sorts of conditions.

-- 
Cheers,
Josh