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
"...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.