Observations of an Internet Middleman (Level3)

Christopher Morrow morrowc.lists at gmail.com
Fri May 16 14:17:43 UTC 2014

On Fri, May 16, 2014 at 7:56 AM, Vinny Abello <vinny at abellohome.net> wrote:

> I think he's questioning why packets from speedtest.comcast.net have CS1 if
> everything is supposedly equal, and what that is used for. A quick Wireshark
> shows that to be true right now running to your Plainfield, NJ speedtest
> site, and my network peers directly with Comcast.

are you measuring inside the (for this) comcast network or after your
I recall that the cable-modem(s) often (by docsis config) impose some
qos markings on the lan-side of the connection.

I think they can do the same on the WAN side for traffic leaving your
site to the tubes... but you probably can't measure that as easily as
with wireshark on your pc.

(also, is there some other equipment between your wiresharker and the
cable-modem? could that equipment be re-marking/marking as well?)

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