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Re: Streaming dead again.
From: odlyzko () dtc umn edu (Andrew Odlyzko)
Date: Wed, 12 Feb 2003 07:44:33 -0600 (CST)

  On Tue, 11 Feb 2003, John Todd wrote:


  > Now, back to the NANOG-ish content:  I know a fundamental change in 
  > technology when I see it, and VOIP is an obvious winner.  VOIP has 
  > been smoldering for a few years, and the sudden growth of various 
  > easy-to-implement SIP proxies and service platforms, plus the sudden 
  > drop in price of SIP hard-phones, is going to push growth 
  > tremendously.  Currently, the underlying technology is UDP that moves 
  > calls around.  This is all well and good until you get thousands, 
  > tens of thousands, hundreds of thousands of calls going at once.  QoS 
  > is, as Bill says, not a problem right now on public networks; I've 
  > used VOIP across at least three exchange or peering sessions (in each 
  > direction, no less!) and suffered no quality loss, even at 80kbps 
  > rates.  However, when a significant percentage of cable and DSL 
  > customers across the country figure this technology out, does this 
  > cause problems for those providers?  Is it worthwhile for large 
  > end-user aggregators to start figuring out how they are going to 
  > offer this service locally on their own networks in order to save on 
  > transit traffic to other peers/providers?  Or is this merely a tiny 
  > bump in traffic, not worth worrying about?

  > More interestingly: what happens to the network when the first 
  > "shared" LD software comes into creation?  Imagine 1/3 (to pick a 
  > worst-case percentage) of  your customers producing and consuming 
  > (possibly) 80kbps of traffic for 5 hours a day as they offer their 
  > local analog lines to anyone who wants to make local calls to that 
  > calling area.

  > Overseas calling I expect will show similar growth.  Nobody wants to 
  > pay $.20 or even $.10 per minute to Asian nations, so as soon as Joe 
  > User figures out how this VOIP stuff works, there will be (is?) a 
  > tendency for UDP increases on inter-continental spans.  Nothing new 
  > here; we've all said this was coming for years.  Now it's finally 
  > possible - is everyone ready?

  > JT


VOIP is likely to cause a financial upheaval in the telecom industry,
because the overwhelming fraction of revenues still comes from voice
services.  However, VOIP is likely to have only a minor impact on
Internet backbones.  The reason is that there simply isn't that much
voice traffic.  Various estimates (such as those in my papers at
<http://www.dtc.umn.edu/~odlyzko/doc/networks.html>) say that already
there is about twice as much US Internet backbone traffic as US long
distance voice traffic, and that is if you count voice as two 64 Kb/s
streams of data.  If you use compression, that goes down even further.

Now introducing flat rate VOIP service will stimulate voice usage
some, but based on various previous experiences, not by enough to
make a quantum difference, especially since (again, based on previous
experiences) it will take a while for VOIP to spread widely.

Andrew Odlyzko

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