Broadband ISPs taxed for "generating light energy"

Roy r.engehausen at
Tue Oct 10 15:17:05 UTC 2006

Michael.Dillon at wrote:
> ..
> Sounds reasonable to me. Since the sale of energy is 
> usually measured in kilowatt-hours, how many kwh of
> energy is transmitted across the average optical fibre
> before it reaches the powereda mplifier in the destination
> switch/router?
> I'd like to see some hard numbers on this.
> The light shining down optical fibres is laser light.
> There exist medical devices which are powered by laser
> light shining through the tissues. There are also some
> types of satellite devices which can receive power from
> ground-based laser beams. The crux of this issue is the
> actual measurement of power transmitted which will turn
> out to be very small.
> --Michael Dillon

A Cisco ZX GBIC produces a max of 4.77 dBm (or less than 4mw).  4mw 
corresponds to 35 watt hours in one year.

However, since the customer must beam back light as part of the exchange 
then you must track the number of pulses in both directions and 
determine the difference.  Some days the customer gets more energy and 
some days it doesn't.  That should affect the tax.

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