An Attempt at Economically Rational Pricing: Time Warner Trial

Sean Donelan sean at donelan.com
Mon Jan 21 22:47:10 UTC 2008


On Mon, 21 Jan 2008, Frank Bulk wrote:
> You're right, the major cost isn't the bandwidth (at least the in the U.S.),
> but the current technologies (cable modem, DSL, and wireless) are thoroughly
> asymmetric, and high upstreams kill the performance of the first and third.

There are symmetric versions for all of those.  But ever since the dialup
days (e.g. 56Kbps modems had slower reverse direction) consumers have 
shown a preference for a bigger number on the box, even if it meant giving 
up bandwidth in the one direction.

For example, how many people want SDSL at 1.5Mbps symmetric versus ADSL at 
6Mbps/768Kbps. The advertisment with the bigger number wins the consumer.

I expect the same thing would happen with 100Mbps symmetric versus 
400Mbps/75Mbps asymmetric.  Consumers would choose 400Mbps over 100Mbps.

> Long-term, fiber avoids the upstream performance issues.

Asymmetric fiber technologiges exists too, and like other technologies 
gives you much more bandwidth than symmetric fiber (in one direction).

The problem for wireless and cable (and probably PON) is using shared 
access bandwidth.  Sharing the access bandwidth lets you advertise much 
bigger numbers than using dedicated access bandwidth; as long as everyone 
doesn't use it. The advantage of dedicated access technologies like 
active fiber (or old fashion T-1, T-3) is your neighbor's bad antics 
don't affect your bandwidth.

Remember the good old days of thicknet Ethernet and what happened when
a single transceiver went crazy, the 10Mbps ethernet coax slowed to a 
crawl for everything connected to it.  The token ring folks may have
been technically correct, but they lost that battle.

There was a reason why IT people replaced shared thicknet/thinnet coax 
Ethernet with dedicated 10Base-T pairs and switches replaced hubs.



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