[IP] Re: Two positions at FCC Comcast Hearing

[David Farber <dave@farber.net>]

________________________________________
From: Craig Partridge [craig@aland.bbn.com]
Sent: Wednesday, February 27, 2008 9:57 AM
To: David Farber; Brad Templeton
Subject: Re: [IP] Two positions at FCC Comcast Hearing

>What is often missed is the question really comes out of this concept of
>the user having spare upstream bandwidth.   Most ISPs sell a flat rate,
>upstream package and as such the bandwidth is sold to the customer and
>is theirs to use to further their usage of the internet.   In the case
>of DSL, the upstream is truly otherwise unused and is lost forever if not
>used.  With DOCSIS and wireless ISPs this is not as true.

Historically it isn't true for DSL either (though perhaps DSLAMs have changed
since I last looked at them closely).  Briefly your DSL link goes to a DSLAM
(usually close to where your local loop terminates) and the DSLAM then
has a link to a router somewhere farther upstream.  The per user
guaranteed bandwidth between DSLAM and router is FAR less (often 1/10th)
of the supposed upstream DSL bandwidth.

Craig

-------------------------------------------