From owner-nanog@merit.edu Sat Mar 26 12:37:15 2005
Date: Sat, 26 Mar 2005 13:35:31 -0500
From: Eric Gauthier <eric@roxanne.org>
To: "Fergie (Paul Ferguson)" <fergdawg@netzero.net>
Cc: nanog@merit.edu
Subject: Re: Clearwire May Block VoIP Competitors> Advancedippipeline - Luật sư của mọi nhà
>"...In what the company claims is an effort to preserve the performance
of its pre-standard WiMAX network, Clearwire says it reserves the right
to prohibit the use of a wide range of bandwidth-hungry applications, a
list that apparently includes VoIP as well as the uploading or
downloading of streaming video or audio, and high-traffic Web site
hosting."Hrm... Isn't a VoIP call realtively low bandwidth?
"*ALL* things are relative." <grin>
I haven't studied
this, but Vonage's site seems to imply that the maximum data rate is 90Kbps
(http://www.vonage.com/help_knowledgeBase_article.php?article=190). I
typically see speeds greater than this from my web browser...
There's a big difference. web browser activity is typically *very* bursty.
'Average' data rate for a any single user is probably in the range of 1%-3%
of the burst peaks.
VoIP, on the other hand, has an "average" utilization that approximates 50%
of the burst rate. In _both directions.
I suspect that that latter factor is a fair part of the "problem". That
the cable company has allocated fairly limited bandwidth for the 'upstream'
direction (from the customer to the head-end). That that 'available'
bandwidth is *grossly* over-subscribed, on the "presumption" that traffic
in that direction would generally be "small", and "infrequent". When those
assupmtions get violated, _everything_ goes to h*ll. <wry grin>
Not just for 'he who' commits the violation, but everybody else who is
sharing that over-subscribed link.
This is what happens when you sell "up to $BIGNUM" connectivity, without
discussing a minimum CCIR promise.
IF a customer does get throttled/blocked, they might have some fun with a
false advertising assertation.